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Study of the Effect of Solar Indices on the Ionosphere Layer of Mars
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               This paper studies the effect of the solar indices (total sunspot no., solar wind density and coronal mass ejection linear speed) on F2- layer electron density, as well as, the comparison of seasonal variations of electron density of F2- layer, NmF2, for Mars at local noontime and for maximum and minimum solar cycles.                  

 Results show that there is an inverse correlation between sunspot number, solar wind density, CME linear speed and ionosphere electron density for Mars, at maximum and minimum solar cycles. This correlation is clear when electron density is at minimum value.                                                                                                                                            

The maximum value of NmF2 was in month 4 (Summer), month 21 (Winter) during maximum solar cycle, and month 1 (Spring), month 24 (Spring) during minimum solar cycle. The minimum value of NmF2 was in month 13 (Autumn) during maximum solar cycle, and month 9 (Summer) during minimum solar cycle. NmF2 was approximately constant in months 1- 8 (Spring and Summer) and gradually decreased in months 9- 13 (Summer and Autumn), then, gradually increased in months 14- 18 (Autumn and Winter) during maximum solar cycle (2012, 2013). In other hand, NmF2 was approximately constant in months 1- 5 (Spring and Summer) and gradually decreased in months 6- 9 (Summer), then, gradually increased in months 10- 16 (Autumn and Winter) during minimum solar cycle (2016, 2017).                                                                                           

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Publication Date
Sun Jun 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Different Methods for Estimating Location Parameter & Scale Parameter for Extreme Value Distribution
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      In this study, different methods were used for estimating location parameter  and scale parameter for extreme value distribution, such as maximum likelihood estimation (MLE) , method of moment  estimation (ME),and approximation  estimators based on percentiles which is called white method in estimation, as the extreme value distribution is one of exponential distributions. Least squares estimation (OLS) was used, weighted least squares estimation (WLS), ridge regression estimation (Rig), and adjusted ridge regression estimation (ARig) were used. Two parameters for expected value to the percentile  as estimation for distribution f

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Publication Date
Wed Apr 25 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Different Estimation Methods for System Reliability Multi-Components model: Exponentiated Weibull Distribution
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        In this paper, estimation of system reliability of the multi-components in stress-strength model R(s,k) is considered, when the stress and strength are independent random variables and follows the Exponentiated Weibull Distribution (EWD) with known first shape parameter θ and, the second shape parameter α is unknown using different estimation methods. Comparisons among the proposed estimators through  Monte Carlo simulation technique were made depend on mean squared error (MSE)  criteria

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