Research ArticleOpen accessIn the abstractApproximation of Experimental Curve of Nonlinear Deformation of DuraluminMoh’d Ishaq Abu HalawaProblem statement: The experimental curves for physically nonlinear deformation of aluminum alloy D-16Т have been approximated in a temperature field. Approach: An analytical approximation variant of plasticity and physical nonlinearity functions was presented and a numerical processing technique of experimental data was described. Results: The corresponding analytical formulas of plasticity functions and nonlinear creep were proposed with mathematically substantiated parameters. … …Journal of Computer Science, Vol. 6, Issue 7 · 31 Jul 2010 · 6,736 accessesView PDFCite
Research ArticleOpen accessIn the abstractSingle Beam Z-Scan Measurements of Nonlinear Refraction and Nonlinear Absorption Coefficients in Silver Nano-FluidEsmaeil Shahriari, W. Mahmood Mat YunusProblem statement: The nonlinear refractive index and nonlinear absorption are two important optical phenomena which are extensively used in optical switching, optical limiting and labeling. Approach: In the present research we had measured nonlinearity of Ag nano-fluid prepared using γ-irradiation method. The measurement was carried out using a single beam z-scan technique. Under a CW laser beam excitation operated at … …American Journal of Engineering and Applied Sciences, Vol. 3, Issue 1 · 31 Mar 2010 · 9,635 accessesView PDFCite
Research ArticleOpen accessIn the abstractNew Directions in Cryptanalysis of Block CiphersDavood RezaeiPour, Mohamad Rushdan Md SaidProblem statement: The algebraic expression of the Advanced Encryption Standard (AES) RIJNDAEL S-box involved only 9 terms. The selected mapping for RIJNDAEL S-box has a simple algebraic expression. This enables algebraic manipulations which can be used to mount interpolation attack. Approach: The interpolation attack was introduced as a cryptanalytic attack against block ciphers. This attack is useful for cryptanalysis using … …Journal of Computer Science, Vol. 5, Issue 12 · 31 Dec 2009 · 7,026 accessesView PDFCite
Research ArticleOpen accessIn the abstractSorption of Phenols: Influence of Groundwater pH and of Soil Organic Carbon ContentSilvia Fiore, Maria Chiara ZanettiProblem statement: Physical and chemical properties of soil, groundwater and pollutants deeply influenced the type and the strength of sorption phenomena involving hydrophobic organic contaminants: Soil fraction of organic carbon (foc) and cation exchange capacity, groundwater pH and pollutants hydrophobicity were with undoubtedly the predominant issues. Approach: In this study an experimental study of the sorption of phenol and 2-nitrophenol … …American Journal of Environmental Sciences, Vol. 5, Issue 4 · 31 Aug 2009 · 7,007 accessesView PDFCite
Research ArticleOpen accessIn the abstractOptical Nonlinear Proreties and Optical Limiting Effect of Metanil YellowR. K. Rekha, A. RamalingamProblem statement: The third order nonlinear optical properties of organic polymers are used in high speed telecommunication, optical limiters and optical computers. The purpose of the study was to determine the third order nonlinear characteristics and optical limiting effect of the organic dye, metanil yellow in liquid and solid medium. Approach: The samples were prepared by dissolving the dye in … …American Journal of Engineering and Applied Sciences, Vol. 2, Issue 2 · 18 Jun 2009 · 7,719 accessesView PDFCite
Research ArticleOpen accessIn the abstractReduced Order Models of a Current Source Inverter Induction Motor DriveIbrahim K. Al-AbbasProblem Statement: The current source inverter induction motor (CSI-IM) drive was widely used in various industries. The main disadvantage of this drive was nonlinearity and complexity. This work was done to develop a simple drive systems models. Approach: The MATLAB/SIMULINK software was used for system modeling. Three reduced models were developed by choosing specific frame, neglecting stator transients and ignoring … …American Journal of Engineering and Applied Sciences, Vol. 2, Issue 1 · 31 Mar 2009 · 7,865 accessesView PDFCite
Research ArticleOpen accessIn the abstractNonlinear Behavior of Single Piles in Jacket Type Offshore Platforms Using Incremental Dynamic AnalysisMohammad Amin Assareh, Behrouz AsgarianThe operation for offshore oil has become an important issue in the recent years. Offshore platforms are some of those structures which are built to withstand environmental and accidental loads during oil exploitation operation. One of the most usual types of these platforms is the Jacket Type Offshore Platform (JTOP) which can be divided into three important parts, which are … …American Journal of Applied Sciences, Vol. 5, Issue 12 · 31 Dec 2008 · 9,299 accessesView PDFCite
Research ArticleOpen accessIn the abstractShort-Term and Medium-Term Load Forecasting for Jordan's Power SystemI. Badran, H. El-Zayyat, G. HalasaSeveral electric power companies are now forecasting electric loads based on conventional methods. However, since the relationship between loads and factors influencing these loads is nonlinear, it is difficult to identify its nonlinearity by using conventional methods. Most of papers deal with 24-h-ahead load forecasting or next day peak load forecasting. These methods forecast the demand power by using forecasted … …American Journal of Applied Sciences, Vol. 5, Issue 7 · 31 Jul 2008 · 7,081 accessesView PDFCite
Research ArticleOpen accessIn the abstractRobust Flight Control Design for a Turn Coordination System with Parameter UncertaintiesAri Legowo, Hiroshi OkuboThis paper presents a method of robust control system design for aircraft flight control systems with the existence of uncertainty parameters such as stability and control derivatives resulted by parameter identification process using real flight test data. A nonlinear model of aircraft turn coordination system is considered where the problem is to find the optimal controller by using the H∞ … …American Journal of Applied Sciences, Vol. 4, Issue 7 · 31 Jul 2007 · 7,498 accessesView PDFCite
Research ArticleOpen accessIn the abstractModelling and Forecasting Volatility of Returns on the Ghana Stock Exchange Using Garch ModelsFrimpong Joseph Magnus, Oteng-Abayie Eric FosuThis paper models and forecasts volatility (conditional variance) on the Ghana Stock Exchange using a random walk (RW), GARCH(1,1), EGARCH(1,1), and TGARCH(1,1) models. The unique ‘three days a week’ Databank Stock Index (DSI) was used to study the dynamics of the Ghana stock market volatility over a 10-year period. The competing volatility models were estimated and their specification and forecast … …American Journal of Applied Sciences, Vol. 3, Issue 10 · 31 Oct 2006 · 7,551 accessesView PDFCite