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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 Jun 01 2021
Journal Name
Journal Of Petroleum Science And Engineering
Top lean zone and cardinal parameters affecting SAGD
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SAGD is a thermal recovery process in which steam oil ratio, SOR, is a key parameter that can affect the economic outcome of the process. Reservoirs with underlying or overlying lean bitumen present challenges for SAGD as they can act as a heat sink. Water has higher heat capacity than the bitumen and thus requires more steam to heat up the reservoir leading to higher SOR. The potential outcome of operating SAGD in these conditions may be lower bitumen rate and higher steam injection rate, both of which affect plant throughput and thus the economic matrix of SAGD. This paper looks at the performance of SAGD process in the presence of top lean bitumen. It will examine the theoretical CSOR that is needed to produce the bitumen with different

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Publication Date
Thu Jun 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Methods of Forecasting Credit Losses in A Sample of Iraqi Banks - A Comparative Analysis
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  The general trend in Iraqi banks is focused towards the application of international financial reporting standards, especially the international financial reporting standard IFRS 9 “Financial Instruments”, in addition to the directives issued on the Central Bank of Iraq’s instructions for the year 2018 regarding the development of expected credit losses models, and not to adhere to a specific method for calculating these losses and authorizing the banks’ departments to adopt the method of calculating losses that suits the nature of the bank’s activity and to be consistent in its use from time to time. The research problem revolves around the different methodologies for calculatin

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Publication Date
Wed Jul 01 2015
Journal Name
Advanced Powder Technology
Characterization of nano-silica prepared from local silica sand and its application in cement mortar using optimization technique
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Publication Date
Thu Sep 03 2015
Journal Name
جامعة بغداد / كلية التربية للعلوم الصرفة - ابن الهيثم
اثر التعليم المدمج والتعلم النشط في تحصيل طلبة قسم الرياضيات في كلية التربية للعلوم الصرفة / ابن الهيثم في مادة المناهج وطرائق التدريس وذكائهم الشخصي
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Publication Date
Wed Feb 20 2019
Journal Name
Political Sciences Journal
Federal and problematic relationship between the center and the region in Iraq
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The US invasion of Iraq in 2003 unleashed the repressed national aspirations of the Kurdish people. After the colonial powers, especially Britain, failed to establish a homeland of scattered Kurds in Iraq, Turkey, Syria and Iran, Iraq's Kurds managed to establish a semi-independent state in the north of the country Which lasted decades against the central authority in Baghdad in protest against what they call the forced integration of Kurds in the Iraqi state, and to obtain more rights and privileges as partners in this country. The federal region in the Kurdistan region of Iraq has become a reality, and it is eager not to strengthen its authority in return for the authority of the central government, but to annex other areas inhabited b

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Publication Date
Fri Oct 12 2018
Journal Name
International Journal Of Medical Research & Health Sciences
A Comparison of Fear Levels of Endodontic Treatment in Iraqi Population
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Introduction: Dental fear is defined as the patient’s specific reaction towards stress related to dental treatment in which the stimulus is unkn..

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Publication Date
Sun Sep 27 2020
Journal Name
Iraqi National Journal Of Nursing Specialties
Evaluation of Health Promotion Program for the Prevention of Epidemics at Primary Health Care Centers in Baghdad City: Comparative Study
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Objective(s): To evaluate and compare between Health Promotion Program for the Prevention of Epidemics at Primary Health Care Centers in Baghdad City.

Methodology: A descriptive study, using the evaluation and comparative approaches, is conducted to evaluate health promotion program for the prevention of epidemics at primary health care centers in baghdad city from October 15th  2019 through March 1st 2020. A purposive, non-probability, sample of (42) health promotion unit officers were recruited from the same number of primary health care centers which were divided into (14) main, (14) sub and (14) family medicine primary health care centers i

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Publication Date
Wed Sep 30 2015
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Correlation of Penetration Rate with Drilling Parameters For an Iraqi Field Using Mud Logging Data
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This paper provides an attempt for modeling rate of penetration (ROP) for an Iraqi oil field with aid of mud logging data. Data of Umm Radhuma formation was selected for this modeling. These data include weight on bit, rotary speed, flow rate and mud density. A statistical approach was applied on these data for improving rate of penetration modeling. As result, an empirical linear ROP model has been developed with good fitness when compared with actual data. Also, a nonlinear regression analysis of different forms was attempted, and the results showed that the power model has good predicting capability with respect to other forms.

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Publication Date
Thu Oct 29 2020
Journal Name
Indian Journal Of Forensic Medicine & Toxicology
Testing the New Parameters affecting The Outcome of Extracorporeal Shockwave Lithotripsy for Upper Ureteric Stones
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Background: Extracorporeal Shock wave lithotripsy (ESWL) is widely used in treating patients with ureteralstones because it is effective, safe, and noninvasive. Based on factors such as size and the location of stones,there is a significant variation in the overall stone-free rate (SFR).Aim of the study: To evaluate the effect of ureteral wall thickness (UWT), stone attenuation, the time fromfirst attack of pain till first session of ESWL and stone/ rib density on the outcome of SWL in the treatmentof upper ureteral stones (UUS).Patient and methods: A prospective study when 127 patients with radio-opaque UUS ranging from 7 to 20mm and treated by ESWL were included in this study. The effect of (stone/ 12th rib) density by KUB, ureter

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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of The College Of Languages (jcl)
(comparative analysis of phraseological units in the lexical-semantic field "on the material of Arabic and Russian languages"): (сопоставительный анализ фразеологических единиц лексико-семантического поля " на материале арабского и русского языков")
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Establishing the systemic character of vocabulary, its relationship with other language systems, their interdependence creates the possibility of a comprehensive scientific study and description of the lexical system of each language, as well as contrastive comparative studies of several languages, including their phraseological composition.

It is known that not all words-components of phraseological units are equivalent in their role in the formation of the semantic content of phraseological units. In this regard, it is necessary to introduce the concept of a lexical dominant. To this we include words, which are kind of centers around which the entire semantic complex of phraseological units, the entire set of its words-componen

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