This article aims to determine the time-dependent heat coefficient together with the temperature solution for a type of semi-linear time-fractional inverse source problem by applying a method based on the finite difference scheme and Tikhonov regularization. An unconditionally stable implicit finite difference scheme is used as a direct (forward) solver. While by the MATLAB routine lsqnonlin from the optimization toolbox, the inverse problem is reformulated as nonlinear least square minimization and solved efficiently. Since the problem is generally incorrect or ill-posed that means any error inclusion in the input data will produce a large error in the output data. Therefore, the Tikhonov regularization technique is applied to obtain stable and accurate results. Finally, to demonstrate the accuracy and effectiveness of our scheme, two benchmark test problems have been considered, and its good working with different noise levels.
Schiff bases were prepared prepared Baaan NMR to some elements of which have contributed to the results of different methods in diagnosis prove structural formulas of compounds prepared
Use of lower squares and restricted boxes
In the estimation of the first-order self-regression parameter
AR (1) (simulation study)
In this study, the first kind Bessel function was used to solve Kepler equation for an elliptical orbiting satellite. It is a classical method that gives a direct solution for calculation of the eccentric anomaly. It was solved for one period from (M=0-360)° with an eccentricity of (e=0-1) and the number of terms from (N=1-10). Also, the error in the representation of the first kind Bessel function was calculated. The results indicated that for eccentricity of (0.1-0.4) and (N = 1-10), the values of eccentric anomaly gave a good result as compared with the exact solution. Besides, the obtained eccentric anomaly values were unaffected by increasing the number of terms (N = 6-10) for eccentricities (0.8 and 0.9). The Bessel
... Show MoreThe family Pholcidae represented by the species Artema doriae )Thorell, 1881) is recorded in Iraq for the first time.So far, 23 families of spiders have been recorded in Iraq.
In this paper, we add a new family and a description of a species belonging to this family in the checklist of Iraqi spider fauna.
During a survey on the helminthic parasites of three species of turtles in the north part of Iraq, five species of nematodes were recorded for the first time in Iraq. They were all found in the intestine. These are, Camallanus microcephalus (Dujardin, 1845) recorvered from the turtle Clemmys caspica; Spironoura japonensis (Yamaguti, 1935) from Triopyx eup¬hraticus and Angusticaecum holopterum (Rudolphi, 1819), and Tachygonetria nicollei (Seurat, 1918) from the turtle Testudo graeca. All of the localities and hosts are newly recorded in Iraq.
In this research، a comparison has been made between the robust estimators of (M) for the Cubic Smoothing Splines technique، to avoid the problem of abnormality in data or contamination of error، and the traditional estimation method of Cubic Smoothing Splines technique by using two criteria of differentiation which are (MADE، WASE) for different sample sizes and disparity levels to estimate the chronologically different coefficients functions for the balanced longitudinal data which are characterized by observations obtained through (n) from the independent subjects، each one of them is measured repeatedly by group of specific time points (m)،since the frequent measurements within the subjects are almost connected an
... Show MoreSimple and rapid spectrophotometric determination of furosemide (FUR) has been investigated .The method is based on acid hydrolysis of FUR to free primary aromatic amine and diazotization followed by coupling with 3, 5 di methyl phenol (3, 5-DMPH) at basic medium. The absorbance was measured at 434 nm, the method was optimized for best condition, and beers’ law is obeyed over the range of 0.4-50 µg.mL-1 with molar absorptivity and sandal’s sensitivity 1.3899 x104 L moL-1 .cm-1 and 0.0238x104 µg.cm-2 respectively. Analysis of solution containing nineteen different concentrations of FUR gave a correlation coefficient of (0.9999) a
... Show MoreThe depth of causative source of gravity is one of the most important parameter
of gravity investigation. Present study introduces the theoretical solve of the
intersection point of the horizontal and vertical gradients of gravity anomaly. Two
constants are obtained to estimate the depth of causative source of gravity anomaly,
first one is 1.7807 for spherical body and the second is 2.4142 for the horizontal
cylinder body. These constants are tested for estimating the depth of three actual
cases and good results are obtained. It is believed that the constants derived on
theoretical bases are better than those obtained by empirical experimental studies.
Trimmed Linear moments (TL-moments) are natural generalization of L-moments that do not require the mean of the underlying distribution to exist. It is known that the sample TL-moments is unbiased estimators to corresponding population TL-moment. Since different choices for the amount of trimming give different values of the estimators it is important to choose the estimator that has minimum mean squares error than others. Therefore, we derive an optimal choice for the amount of trimming from known distributions based on the minimum errors between the estimators. Moreover, we study simulation-based approach to choose an optimal amount of trimming and maximum like hood method by computing the estimators and mean squares error for range of
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