Research ArticleOpen accessIn the abstractSome Fast Methods for Fitting Some One-parameter Spatial ModelsR. J. MartinIt is common in geographic modelling to use a one-parameter spatial model to specify the inverse covariance matrix in terms of I-βW, for some known matrix W. Exact Gaussian maximum likelihood estimation of β requires evaluation of the determinant of the covariance matrix. For large data sets, this evaluation of the determinant can be slow and good approximations can be … …Journal of Mathematics and Statistics, Vol. 1, Issue 4 · 31 Dec 2005 · 6,066 accessesView PDFCite
Research ArticleOpen accessIn the abstractInverse Correlations for Multiple Time Series and Gaussian Random Fields and Measures of Their Linear DeterminismR.J. Bhansali, L. IppolitiFor a discrete-time vector linear stationary process, {X(t)}, admitting forward and backward autoregressive representations, the variance matrix of an optimal linear interpolator of X(t), based on a knowledge of {X(t-j), j≠0}, is known to be given by Ri(0)-1 where Ri(0) denotes the inverse variance of the process. Let A=Is-1Ri(0)ˉ1R(0)ˉ1, where R(0) denotes the variance matrix of {X(t)} and Is an … …Journal of Mathematics and Statistics, Vol. 1, Issue 4 · 31 Dec 2005 · 6,424 accessesView PDFCite
Research ArticleOpen accessIn the abstractSpeaker Recognition Using Spectral Cross-correlation: A Fast AlgorithmZoubir HamiciThis study presents an original algorithm for computing the cross-correlation function applied for speech recognition A spectral correlation estimation algorithm based on the comparing the magnitude spectrum of the two signals is presented. The number of samples is reduced by a factor of two, after eliminating the image spectrum. A moving average filter is used to smooth the magnitude spectrum … …Journal of Computer Science, Vol. 1, Issue 2 · 19 Oct 2005 · 5,013 accessesView PDFCite
Research ArticleOpen accessIn the abstractNonlinear Growth Models for Modeling Oil Palm Yield GrowthAzme Khamis, Zuhaimy Ismail, khalid Haron, Ahmad Tarmizi MohammedThis study provided the basic needs of parameters estimation for nonlinear growth model such as partial derivatives of each model, determination of initial values for each parameter and statistical tests of industrial usage. Twelve nonlinear growth models and its partial derivatives for oil palm yield growth are presented in this study. The parameters are estimated using the Marquardt iterative method … …Journal of Mathematics and Statistics, Vol. 1, Issue 3 · 30 Sep 2005 · 15,101 accessesView PDFCite
Research ArticleOpen accessIn the abstractContribution of Advective and Non-advective Heat Fluxes to the Heat Budget of a Shallow LagoonRodríguez-Rodríguez MiguelThe heat budget in a shallow lagoon has been established from field measurements at a bihourly scale. Information on the main advective and non-advective heat fluxes were collected during year 2003 at Nueva lagoon (Almería, Southern Spain). Heat storage data was obtained from a thermistor chain located in the deepest part of the lagoon and meteorological information was acquired using … …American Journal of Environmental Sciences, Vol. 1, Issue 2 · 30 Jun 2005 · 6,491 accessesView PDFCite
Research ArticleOpen accessIn the abstractValidation of Some Bridge Pier Scour Formulae Using Field and Laboratory DataThamer A. Mohamed, Megat J.M.M. Noor, Abdul H. Ghazali, Bujang B.K. HuatEstimation of maximum local scour depth at the bride pier site is necessary for the safety and economy of the designed bridge. Numerous formulae are available and almost all of these formulae were developed based on laboratory data. Validation of these formulae is necessary in order to ascertain which of the formulae will give a reasonable estimate of the local … …American Journal of Environmental Sciences, Vol. 1, Issue 2 · 30 Jun 2005 · 7,826 accessesView PDFCite
Research ArticleOpen accessIn the abstractImpulse Volt-Time Characteristics of Oil and OIP InsulationS. Venkatesan, S. UsaEstimation of insulation strength of transformer oil and Oil Impregnated Paper (OIP) insulation, which constitutes major portion of insulation in power transformer, is an important task. Also, it is often necessary to evaluate the breakdown strength of oil and OIP under non-standard impulse voltages, since the oil and OIP insulation is subjected to non-standard waveshapes between inter-disc and inter-turn insulation. … …American Journal of Applied Sciences, Vol. 2, Issue 2 · 28 Feb 2005 · 7,241 accessesView PDFCite
Research ArticleOpen accessIn the abstractDevelopment of Ecological Criteria of Noise Control With Application of AbsorbentsM. A. Al-NawaflehThe operation conditions of the industrial equipment, acoustic parameters essentially depend on type of the sound field (free, diffuse or mixed). Besides the effect of the noise control of the machine itself, the field type also important, which in turn depends on the degree and quality of acoustic preparation of the workshop. The criteria is an estimation of applicability broadband … …American Journal of Applied Sciences, Vol. 2, Issue 1 · 31 Jan 2005 · 6,805 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