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A Comparative Study for Estimate Fractional Parameter of ARFIMA Model
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      Long memory analysis is one of the most active areas in econometrics and time series where various methods have been introduced to identify and estimate the long memory parameter in partially integrated time series. One of the most common models used to represent time series that have a long memory is the ARFIMA (Auto Regressive Fractional Integration Moving Average Model) which diffs are a fractional number called the fractional parameter. To analyze and determine the ARFIMA model, the fractal parameter must be estimated. There are many methods for fractional parameter estimation. In this research, the estimation methods were divided into indirect methods, where the Hurst parameter is estimated first, and then the fractional integration parameter is estimated from it by a relation between them. As for direct methods, the fractional integration parameter is estimated directly without relying on Hurst's parameter, and most of them are semi parametric methods. In this paper, some of the most common direct methods were used to estimate the fraction modulus namely (Geweke-Porter-Hudak, Smoothed Geweke-Porter-Hudak, Local Whittle, Wavelet and weighted wavelet), using simulation method with different value of (d) and different size of time series. The comparison between the methods was done using the mean squared error (MSE). It turns out that the best methods to estimate the fractional parameter is (Local Whittle).

      The ARFIMA model was generated by a function programmed by the MATLAB statistical program

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Publication Date
Fri Jan 01 2021
Journal Name
Brazilian Dental Science
Assessing the level and diagnostic accuracy of osteopontin and oral health status in periodontitis patients with/without Type-2 Diabetes Mellitus
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Publication Date
Sun Jan 30 2022
Journal Name
Iraqi Journal Of Science
Synthesis, Characterization, Theoretical Studies and Bioactivity of Pd(II), Rh(III), Ru(III) and Pt(IV) Complexes with 1,8-Naphthalimide Derivative
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A New Mannich base [N-(4-morpholinomethyl)-1,8-naphthalimide] (L), was synthesized and characterized by C.H.N analysis, FTIR, UV-Vis and 1HNMR spectral analysis. Metal ion complexes of (L) with Pt(IV), Rh(III), Ru(III) and Pd(II) ions were prepared and characterized by FT-IR, and UV-Vis spectroscopy, elemental analysis (C.H.N), flame atomic absorption techniques as well as magnetic susceptibility and conductivity measurements. The results showed that metal ion complexes for all complexes were found in [1:2] [M:L] ratio except for Pd(II) complex which was found in [1:1] [M:L] ratio. Hyperchem-8 program has been used to predict structural geometries of the (L) and it's complexes in gas phase. The electrostatic potential (EP) of the (L) was

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Publication Date
Sat Aug 31 2019
Journal Name
Iraqi Journal Of Physics
The Effect of Laser And Thermal Treatment on the Hardness and Adhesion Force on the Cermet Coating By Thermal Spray Technique
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Ceramic coating compose from a ceramic mixture (MgO, Al2O3) and metall (Al-Ni) were produced by Thermal Spray Technique. The mixed ratio of used materials Al:Ni (50%) and 40% of Al2O3 and 10% MgO. This mixture was spray on a stainless steel substrate of type (316 L) by using thermal spray with flame method and at spraying distances (8, 12, 16 and 20) cm, then the prepared films were treated by laser and thermal treatment. After that performing a hardness and adhesion tests were eximined. The present study shows that the best value of the thermal treatment is 1000 ℃ for 30 mint; the optimum spray distance is 12 cm and most suitable laser is 500 mJ where the microscopic and mechanical character

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Publication Date
Fri Jan 01 2016
Journal Name
Iraqi Journal Of Science
Effect of growth media components and growth condition on indole - 3 - acetic acid (IAA) production by Pseudomonas putida isolated from soil
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Publication Date
Mon Mar 01 2021
Journal Name
World Heart Journal
Change in Left Ventricular Size and Ejection Fraction in Patients at Rest vs. Stress with Different Degrees of Ischemic Heart Failure
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Background and Aim. Coronary artery disease (CAD) is a major risk factor for the progression to heart failure (HF), which is associated with an increase in left ventricular volume (LVV). This study aims to measure ventricular function and myocardial perfusion imaging markers of the left side of the heart, which can be performed with injection of a 99mTc at stress and rest by using single-photonemission-computed-tomography (SPECT). Subject and methods. The study included 121 patients with CAD, comprising 53 females and 68 males with ages between 25 to 88 years and 265 healthy subjects comprising 84 males and 181 females. All patients and healthy subjects volunteered to participate in this study. They were classified according to

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Publication Date
Fri Mar 01 2019
Journal Name
Iraqi Journal Of Physics
Structural and optical properties of Fe- doped ZnO thin films prepared by Sol–Gel spin coating process and their photocatalytic activities
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Pure and Fe-doped zinc oxide nanocrystalline films were prepared
via a sol–gel method using -
C for 2 h.
The thin films were prepared and characterized by X-ray diffraction
(XRD), atomic force microscopy (AFM), field emission scanning
electron microscopy (FE-SEM) and UV- visible spectroscopy. The
XRD results showed that ZnO has hexagonal wurtzite structure and
the Fe ions were well incorporated into the ZnO structure. As the Fe
level increased from 2 wt% to 8 wt%, the crystallite size reduced in
comparison with the pure ZnO. The transmittance spectra were then
recorded at wavelengths ranging from 300 nm to 1000 nm. The
optical band gap energy of spin-coated films also decreased as Fe
doping concentra

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Publication Date
Wed Dec 29 2021
Journal Name
Modern Sport
Creative behavior and its relationship to the administrative leadership of secondary school principals in Al- Karkh/2 district in Baghdad governorate
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The importance of research lies in the school administration and that the school is the main cell of the educational system and its ultimate goal, and therefore modern education requires the presence of sophisticated leaders represented in educational administration at various levels. Administrative leaderships and the two researchers' belief that the institution’s ability and success or failure depend on a special type of leader who is highly effective and efficient, directing workers ’behavior towards creativity and achievement in order to achieve the goals of the institution in serving the educational bodies, increasing the effectiveness of leadership and developing the creative behavior of secondary school principals in

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Publication Date
Thu Nov 30 2023
Journal Name
Iraqi Geological Journal
Multiple and Coherent Noise Removal from X-Profile 2D Seismic Data of Southern Iraq Using Normal Move Out-Frequency Wavenumber Technique
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Multiple eliminations (de-multiple) are one of seismic processing steps to remove their effects and delineate the correct primary refractors. Using normal move out to flatten primaries is the way to eliminate multiples through transforming these data to frequency-wavenumber domain. The flatten primaries are aligned with zero axis of the frequency-wavenumber domain and any other reflection types (multiples and random noise) are distributed elsewhere. Dip-filter is applied to pass the aligned data and reject others will separate primaries from multiple after transforming the data back from frequency-wavenumber domain to time-distance domain. For that, a suggested name for this technique as normal move out- frequency-wavenumber domain

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Publication Date
Thu Jan 27 2022
Journal Name
Journal Of Population Therapeutics And Clinical Pharmacology
Is adding an Oral Antibiotic with the Topical Antibiotic-Steroid Useful in Treatment of Uncomplicated Acute Otitis Externa in Immunocompetent Patients?
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Publication Date
Sun Apr 30 2023
Journal Name
Iraqi Journal Of Science
Intra Specific Relationships and Biochemical Composition of Laportea Aestuans (L.) Chew, Sida Rhombifolia L. And Commelina Verginica L. in Lagos State
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Laportea aestuans L. (Chew), Commelina virginica (L.) and Sida rhombifolia (L.) are common wild plants used in treating several ailments including diarrhea, dysentery, hernia, oedema, ulcers and many more in traditional African medicine especially, Nigeria. The potentials of Random Amplified polymorphic DNA (RAPD) primers in delimiting intra-specific variation in L. aestuans, C. virginica and S. rhombifolia was assessed using three RAPD primers. Plant and soil samples were collected from 19 local government areas in Lagos State and assessed for genetic and biochemical relationships. A total of 56 bands were produced of which 44 were polymorphic. Maximum number of bands (21) was produced by OPY

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