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jeasiq-1598
Comparison of classical method and optimization methods for estimating parameters in nonlinear ordinary differential equation
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  This study is concerned with the estimation of constant  and time-varying parameters in non-linear ordinary differential equations, which do not have analytical solutions. The estimation is done in a multi-stage method where constant and time-varying parameters are estimated in a straight sequential way from several stages. In the first stage, the model of the differential equations is converted to a regression model that includes the state variables with their derivatives and then the estimation of the state variables and their derivatives in a penalized splines method and compensating the estimations in the regression model. In the second stage, the pseudo- least squares method was used to estimate the constant parameters. In the third stage, the remaining constant parameters and the time-varying parameters are estimated by using a semi-parametric regression model. This method is compared with the optimization method, which depends on the algorithm of differential evolution algorithm to estimate unknown parameters. The comparison was made using simulations. The results showed that the results were better to the method based on the differential evolution algorithm.

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Publication Date
Tue Mar 01 2022
Journal Name
Materials Today Communications
Fe2O3-SiO2 nanocomposite film-induced high nonlinear effect for multiwavelength mode-locked generation in ytterbium-doped fiber laser
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In this work, the possibility of a multiwavelength mode-locked fiber laser generation based on Four-Wave Mixing (FWM) induced by Fe2O3-SiO2 nanocomposite material is investigated for the first time. A multiwavelength mode-locked pulses fiber laser are generated from Ytterbium–doped fiber laser (YDFL) due to the combined action of high nonlinear absorption and high refractive coefficients of Fe2O3-SiO2 nanocomposite incorporated inside YDFL ring cavity. Up to more than 20 lasing lines in the 1040–1070 nm band with an equally lines separation of ~0.6 nm have been observed by just simple variation of passive modulation of the state of the polarization and the pump power altogether. Moreover, a passively mode-locked operation of YDFL laser

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Publication Date
Sat Mar 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Selection of Suitable Drilling Parameters for obtaining high Rate of Penetration in Majnoon Oilfield
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Several directional wells have been drilled in Majnoon oilfield at wide variation in drilling time due to different drilling parameters applied for each well. This technical paper shows the importance of proper selection of the bit, Mud type, applied weight on Bit (WOB), Revolution per minute (RPM), and flow rate based on the previous wells drilled. Utilizing the data during drilling each section for directional wells that's significantly could improve drilling efficiency presented at a high rate of penetration (ROP). Based on the extensive study of three directional wells of 35 degree inclination (MJ-51, MJ-52, and MJ-54) found that the applied drilling parameters for MJ-54 and the bit type within associated drilling parameters to drill

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Publication Date
Sat Sep 30 2017
Journal Name
College Of Islamic Sciences
Ruling on questioning children by the security authorities: (Comparative Study between Sharia and Law)
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Some of the issues that have become common in our society recently after the Americans entered our country and were rubbed by some security agencies: obtaining some information from children, and the serious consequences that may lead to the lives of innocent people, became common interrogation of some security agencies and rely on their words.
There are significant cases where their testimony needs to be heard, such as their presence in some places where incidents are not witnessed by others, such as schools or being witnesses to certain crimes.
I saw the study of this case in the light of Sharia and law

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Publication Date
Thu Mar 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Administrative competencies in many of Iraqi public Organizations: comparative study.
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Competencies topic in general , and Administrative competencies in specific, are considered as important subject in the contemporary administrative literature in all countries as well as in public and privet Organizations. For this reason, we have need to study those competencies in many Iraqi Organizations.

Two Organizations wer chosen for this research one of them is the Institution of taxation, and the other is the General company of Electric the data and information related to the research have been collected by desined questioner which has been given to a sample of (50) persions divided eqully between the two maintioned organizations.

The results of the study had differences

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
استخدام أسعار الأسهم العادية في قياس كفاءة الإدارة المالية في عينة من الشركات العراقية
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تهدف الدراسة الحالية الى التعرف على مدى فاعلية استخدام اسعار اسهم الشركات العادية المتداولة في اسواق راس المال لقياس كفاءة الادارة المالية، وذلك بعد دراسة اهم العوامل المؤثرة على هذه الاسعار، بالاضافة الى محاولة اعطاء فكرة مختصرة عن مفهوم الاسهم العادية وبعض الامور المتعلقة بها، اما الجانب التطبيقي فقد تم اخذ اسعار الاسهم العادية لعينة من الشركات العراقية واجراء مقارنة بينها وبين القيمة الدفترية لها ومن

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Publication Date
Sun Dec 07 2014
Journal Name
Baghdad Science Journal
Oscillations of First Order Neutral Differential Equations with Positive and Negative Coefficients
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Oscillation criterion is investigated for all solutions of the first-order linear neutral differential equations with positive and negative coefficients. Some sufficient conditions are established so that every solution of eq.(1.1) oscillate. Generalizing of some results in [4] and [5] are given. Examples are given to illustrated our main results.

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
numerical solution of nth order linear dealy differential
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in this paper fourth order kutta method has been used to find the numerical solution for different types of first liner

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Publication Date
Tue Jun 03 2025
Journal Name
Sar Journal Of Pathology And Microbiology
The Relation between Tumor Infiltrating Lymphocyte and Classical Tumor Staging in Colorectal Carcinoma (Semi-Quantitative Study by Immun histochemistry in a Group of Iraqi Patients)
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Inflammatory response had a role in cancer progression, presence of noticeable inflammation within the tumor and its margin may play an important prognostic role in colorectal carcinoma.

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Publication Date
Tue Jan 01 2019
Journal Name
Indian Journal Of Public Health Research & Development
Anticardiolipin Antibodies in Comparison to B-HCG Titer and Serum Progesterone as Indicator for Ectopic Pregnancies
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Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
Samples of Al Samarqandi’s Selection in some of Washing Laws and the touch of the Grecians Quran in his book (The scholars’ Masterpiece)
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The Research is interested in the detailed comparative study of certain selection of
Imam Alsamarqandi in some subjects of washing and touching the Gracious Quran.
The value of this study is that it is related to one aspect of the duties obliged on Muslim
like parity.
The study has tried to collect certain scholars’ opinions of eight doctrines with the
selection of Alsamarqandi to make a comp arson between them and to show how
Alsamarqandi is able to create legal laws from his sources to lead the researchers nto have
knowledge about the syllabi of the famous scientists.
Finally we ask God to bless to what is right and to accept this study and make it part of
our good deeds, Ameen.

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