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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
Mon Nov 27 2023
Journal Name
Korean Journal Of Orthodontics
Effectiveness of laser-engineered copper-nickel titanium versus superelastic nickel-titanium aligning archwires: A randomized clinical trial
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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Removal of Dissolved Trivalent Chromium Ions from Contaminated Wastewater using Locally Available Raw Scrap Iron-Aluminum Waste
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The present study is to investigate the possibility of using wastes in the form of scrap iron (ZVI) and/ or aluminum ZVAI for the detention and immobilization of the chromium ions in simulated wastewater. Different batch equilibrium parameters such as contact time (0-250) min, sorbent dose (2-8 g ZVI/100 mL and 0.2-1 g ZVAI/100 mL), initial pH (3-6), initial pollutant concentration of 50 mg/L, and speed of agitation (0-250) rpm were investigated. Maximum contaminant removal efficiency corresponding to (96 %) at 250 min contact time, 1g ZVAI/ 6g ZVI sorbent mass ratio, pH 5.5, pollutant concentration of 50 mg/L initially, and 250 rpm agitation speed were obtained.

The best isotherm model for the batch single Cr(III) uptake by ZVI

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Publication Date
Mon Feb 04 2019
Journal Name
Iraqi Journal Of Physics
Temperature effect on optical properties of nickel (ii) phthalocyanine tetrasulfonic acid tetrasodium salt (NiPcTs) organic thin films
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This study describe the effect of temperature on the optical
properties of nickel(ii) phthalocyanine tetrasulfonic acid tetrasodium
salt (NiPcTs) organic thin films which are prepared by spin coating
on indium tin oxide (ITO-glass). The optical absorption spectra of
these thin films are measured. Present studies reveal that the optical
band gap energies of NiPcTs thin films are dependent on the
annealing temperatures. The optical band gap decreases with increase
in annealing temperature, then increased when the temperature rising
to 473K. To enhance the results of Uv-Vis measurements and get
more accurate values of optical energy gaps; the Photoluminescence
spectra of as-deposited and annealed NiPcTs thin fi

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Publication Date
Sat Feb 05 2022
Journal Name
Applied Nanoscience
RETRACTED ARTICLE: The impact of fear on a stage structure prey–predator system with anti-predator behavior
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A prey-predator interaction model has been suggested in which the population of a predator consists of a two-stage structure. Modified Holling's disk equation is used to describe the consumption of the prey so that it involves the additional source of food for the predator. The fear function is imposed on prey. It is supposed that the prey exhibits anti-predator behavior and may kill the adult predator due to their struggle against predation. The proposed model is investigated for existence, uniqueness, and boundedness. After determining all feasible equilibrium points, the local stability analyses are performed. In addition, global stability analyses for this model using the Lyapunov method are investigated. The chance of occurrence of loc

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Publication Date
Sun Sep 07 2008
Journal Name
Baghdad Science Journal
Study the effect by CO2 laser on some optical properties of (Cd) thin film doping by Ni
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In this research study the effect of irradiation by (CW) CO2 laser on some optical properties of (Cds) doping by Ni thin films of (1)µm thickness has been prepared by heat evaporation method. (X-Ray) diffraction technique showed the prepared films before and after irradiation are ploy crystalline hexagonal structure, optical properties were include recording of absorbance spectra for prepared films in the range of (400-1000) nm wave lengths, the absorption coefficient and the energy gap were calculated before and after irradiation, finally the irradiation affected (CdS) thin films by changing its color from the Transparent yellow to dark rough yellow and decrease the value absorption coefficient also increase the value of energy gap.

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Publication Date
Fri Mar 31 2017
Journal Name
Journal Of Engineering
Cultivation of Chlorella Vulgaris Using Airlift Photobioreactor Sparged with 5%CO 2 -Air as a Biofixing Process
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The present paper addresses cultivation of Chlorella vulgaris microalgae using airlift photobioreactor that sparged with 5% CO 2 /air. The experimental data were compared with that obtained from bioreactor aerated with air and unsparged bioreactor. The results showed that the concentration of biomass is 0.36 g l -1  in sparged bioreactor with CO2/air, while, the concentration of biomass reached to 0.069 g l -1  in the unsparged bioreactor. They showed also that aerated  ioreactor.with CO2/air gives more biomass production even the bioreactor was aerated with air. This study proved that application of sparging system for  ultivation of Chlorella vulgaris microalgae using either CO2/air mixture or air has a significant

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Publication Date
Wed Jul 11 2018
Journal Name
دراسات تربوية
Understanding the nature of the scientific endeavor among chemistry teachers according to the Educational Reform Project 2061
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Publication Date
Fri Mar 25 2022
Journal Name
Asian Journal Of Biochemistry, Genetics And Molecular Biology
Evaluation of the Simple Sequence Repeats to Work as a Phase Variation with the Neisseria meningitidis Genome
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Background: The most crucial mechanism of genetic variation in N. meningitidis is the slipped strand mispairing, this mechanism generates Phase variation using simple sequence repeat (SSR) and is commonly used by the N. meningitidis to escape the immune system despite its function in eradicating the pathogenic and commensal bacteria. Some of simple sequence repeats (SSRs) that located within the genome works as phase variation while other SSRs have no role in generating phase variation mechanisms. Therefore, Aim: the main goal of the current in silico study was to detect the probability of SSR to enroll with phase variation for the entire N. meningitidis genome. Methods: Different criteria were used to judge SSR as

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Publication Date
Fri Mar 21 2025
Journal Name
The Indonesian Journal Of Community And Occupational Medicine
Observance of the Adherence to Antibiotic Prescriptions by Iraqi Dental Patients: A Different Perspective on Antimicrobial Resistance
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Background: The excessive use and abuse of antibiotics contribute to bacterial resistance, raising the risk of complications and treatment failures. This study investigates adherence to antibiotic prescriptions among Iraqi dental patients, highlighting implications for antimicrobial resistance.Objective: To assess adherence levels and identify factors influencing antibiotic therapy compliance among dental patients.Methods: A cross-sectional survey was conducted in which adult dental patients aged 18 and older, who had been prescribed antibiotics within the past year, participated. The modified Morisky Medication Adherence Scale-8 items was used to evaluate adherence, and data were analyzed with IBM SPSS Statistics software V26.Results: Amon

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Publication Date
Sun Sep 04 2016
Journal Name
Baghdad Science Journal
Evaluate the Effectiveness of Agaricus bisporus (Spawn) on Control Damping – off Caused by Pythium aphanidermatum on Cucumber
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This study was conducted to test the effectiveness of Agaricus bisporus inoculums (spawn) in the ratio of (0.25, 0.5 and 1%) v/v to control Pythium aphanidermatum fungus the causal agent of damping- off disease of cucumber plant. results showed the ability of A. bisporus fungus to protect the seedlings from incidence by P. aphanidermatum . all treatments of edible fungus inoculums were significantly different from pathogen treatment after 15 day of planting and there was no significant difference found from control treatment (without pathogen) . the successful of A. bisporus was continued to protect the seedlings after 30 and 45 day after planting. The numbers of seedlings were (8, 7.25 & 7.25) respectively compared to 5.5 seedlings in con

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