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jih-447
Estimate AR(3) by Using Levinson-Durbin Recurrence & Weighted Least Squares Error Methods
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In this study, we investigate about the estimation improvement for Autoregressive model of the third order, by using Levinson-Durbin Recurrence (LDR) and Weighted Least Squares Error ( WLSE ).By generating time series from AR(3) model when the error term for AR(3) is normally and Non normally distributed and when the error term has ARCH(q) model with order q=1,2.We used different samples sizes and the results are obtained by using simulation. In general, we concluded that the estimation improvement for Autoregressive model for both estimation methods (LDR&WLSE), would be by increasing sample size, for all distributions which are considered for the error term , except the lognormal distribution. Also we see that the estimation improvement for WSLE method, depends on the value for the Forgetting Factor parameter (α),which haave value less than one(i.e. 1) ( α< ). The estimate is improved for large value for parameterα exactly at 0.99 α= .Finally, we used the estimation methods (LDR&WLSE) for real data.

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
3-D Seismic Survey Study of Faults System in Balad Oil Field – Center of Iraq
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3D seismic reflection structural study of (250) km² of Balad Oil field located in central part of Iraq within Salah Al-din province (Balad area) was carried out.
Faults were picked using instantaneous phase attribute of seismic sections and variance attribute of seismic time slices across 3D seismic volume.
A Listric growth normal fault is affecting the succession of Cretaceous Formation and cut by strike slip fault. In addition, minor normal faults (Dendritic and tension faults) are developed on the listric normal growth fault. As a result, a major graben is separated by Strike slip fault into two parts (north and south parts) and trend in NW-SE direction.

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Publication Date
Mon Dec 01 2014
Journal Name
Agricultural Mechanization In Asia, Africa And Latin America
Determination of the suitability period of S-3 diesel oil when used in tractor engines
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The diesel oil type S-3 specified for diesel engine has limited the suitability for diesel trucks for 8000 km, but didn't clarify its suitability if used in tractor engines.It is known that the work style of farm tractor differs from that of other vehicles where tractors are used for all the activities in sever conditions and under the complete usage of the available power and capability, so there is no sign or indication of the usage period of this oil in tractor's engine. The oil has been used on Cirta C6806 tractors. The manual book of the tractor's engine, Deutz recommends changing the oil every 100 hrs. Therefore the main goal of this research is to give the recommended working hours for S-3 diesel oil when used in farm tractor engines

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Scopus (2)
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Publication Date
Sun Apr 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Classification and Construction of (k,3)-Arcs on Projective Plane Over Galois Field GF(9)
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  In this work, we construct and classify the projectively distinct (k,3)-arcs in PG(2,9), where k ≥ 5, and prove that the complete (k,3)-arcs do not exist, where 5 ≤ k ≤ 13. We found that the maximum complete (k,3)-arc in PG(2,q) is the (16,3)-arc and the minimum complete (k,3)-arc in PG(2,q) is the (14,3)-arc. Moreover, we found the complete (k,3)-arcs between them.

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Publication Date
Sun Apr 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Classification and Construction of (k,3)-Arcs on Projective Plane Over Galois Field GF(7)
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  The purpose of this work is to study the classification and construction of (k,3)-arcs in the projective plane PG(2,7). We found that there are two (5,3)-arcs, four (6,3)-arcs, six (7,3)arcs, six (8,3)-arcs, seven (9,3)-arcs, six (10,3)-arcs and six (11,3)-arcs.         All of these arcs are incomplete.         The number of distinct (12,3)-arcs are six, two of them are complete.         There are four distinct (13,3)-arcs, two of them are complete and one (14,3)-arc which is incomplete.         There exists one complete (15,3)-arc.
 

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF SOME (2-AMINO-5-THIOL-1, 3, 4-THIADIAZOLE DERIVATIVES
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Five derivatives of thiadiazole were prepared with aldehydes and alkyl halides, compoundA: 2-amino-5-thiol-1,3,4- thiadiazole, compound B :2-(o-hydroxybenzylidine)amino-5-thiol-1,3,4-thiadiazole, compoundC: 2(2-butan-lidine)amino-5-thiol-1,3,4-thiadiazole, compound E: 2- amino-5-(2-Propanylthio)-1,3,4-thiadiazol) and compound F:2(o-chlorobenzylamino)-5-(2-propanyl thio)-1,3,4 thiadiazol. All prepared compounds were diagnosed by (IR) and (UV) Spectroscopy. All of those compounds were screened for their anti-microbial activity in vitro. The results show that most of the compounds A, B, C exhibited moderate to good activity against Gram-positive bacteria and the same compound exhibit low to moderate activity on most gram-negative bacte

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Publication Date
Sat Jun 09 2018
Journal Name
Journal Of Molecular Structurs
Mesogenic materials incorporating 4H-1,2,4-triazol-3-thiol moiety: Synthesis, characterization and liquid crystals study
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Three series of monomers, polymers and thioester cyclic compounds containing 4H-1,2,4-triazol-3-thiol moiety were synthesized and examined for their liquid crystalline properties. All monomers, polymers and thioester compounds were characterized by elemental analysis and FTIR, 1 H-NMR and mass spectroscopy. The phase transition and mesomorphic properties were investigated by polarized optical microscope (POM) and differential scanning calorimetry (DSC). The monomer with terminal phenyl substituent display dimorphism nematic and smectic A (SmA) mesophases. The corresponding polymers derived from acrylic and phenyl acrylic acid monomers show nematic mesophase. The only thioester cyclic compound derived from terephtaloyl chloride show nemati

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Scopus (13)
Scopus
Publication Date
Mon Dec 23 2019
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Effects of Omega-3 Co-Administered with Therapeutic Dose of lornoxicam on Male Rats' Liver
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The purpose of this study was to investigate the effect of omega-3 poly unsaturated fatty-acids co-administered with the therapeutic dose of lornoxicam on liver of healthy rats. Twenty-eight adults male rats weighing 180-200g were used in this study and the animals were randomly divided into four groups of seven rats each. Group I: negative control/rats intraperitoneally injected with normal saline in a dose 5ml/kg/day; Group II: rats intraperitoneally injected with lornoxicam at dose 0.7 mg/kg/day; Group III: rats orally-administered omega-3 only at a dose 185mg/kg/day; Group IV: rats co-administered omega-3 (185mg/kg/day) orally and in

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Publication Date
Wed Jan 01 2020
Journal Name
Systematic Reviews In Pharmacy
Synthesis of New Ibuprofen Derivatives Containing (Oxothiazolidin-3-yl) Amino Moiety with Expected Biological Activity
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Nonsteroidal anti-inflammatory drugs (NSAIDs) are drugs that help reduce inflammation, which often helps to relieve pain. In this research new ibuprofen oxothiazolidnone derivatives were synthesized from the reaction of Schiff base derivatives of Ibuprofen with mercapto acetic acid VI a-c, to improve the potency and to decrease the drug's potential side effects, a new series of 4-thiazolidinone derivatives of ibuprofen was synthesized VI a-c . The characterizations of the compounds were identified by using FTIR, 1HNMR technique and by measuring the physical properties.

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Scopus (3)
Scopus
Publication Date
Sun Aug 13 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Designing A Computer Program to Determine the Points and Planes in 3-Dimensional Projective Space
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  The purpose of this work is to determine the points and planes of 3-dimensional projective space PG(3,2) over Galois field GF(q), q=2,3 and 5 by designing a computer program.

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Publication Date
Tue Feb 13 2018
Journal Name
Chemistry Central Journal
Effect of crosslinking concentration on properties of 3-(trimethoxysilyl) propyl methacrylate/N-vinyl pyrrolidone gels
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Scopus (31)
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