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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
Thu Feb 07 2019
Journal Name
Iraqi Journal Of Laser
Investigation of Nonlinear Optical Characteristics of the Multi-Wall Carbon Nanotubes (MWCNT's) Suspensions using Nonlinear Self-Diffraction of a Laser Beam
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Nonlinear diffraction patterns can be obtained by focusing a laser beam through a thin slice of the material. Here, we investigated experimentally the formation of the far field nonlinear diffraction patterns of cw laser beam at 532 nm passing through a quartz cuvette containing multi-wall carbon nanotubes (MWCNT's) suspended in acetone and in DI water at concentrations of 0.030.wt.%, 0.045 wt.%, 0.060 wt.%, and 0.075 wt.%. Our results show that increasing the concentration of both types of suspensions (MWCNTs in acetone and MWCNTs DI water) led to increase in the number of pattern rings which indicates an increase in their nonlinear refractive indices. Moreover, MWCNTs DI water suspension at a concentration of 0.075 wt. % was more effic

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Publication Date
Thu Mar 30 2023
Journal Name
Iraqi Journal Of Science
Electrochemical Study for the Effect of Simvastatin and Atorvastatin on Coenzyme Q10 by Differential Pulse Polarography Using Mercury Drop Electrode
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Statin drugs act by inhibiting the enzyme HMG-CoA reductase which is responsible for manufacture of cholesterol and the biosynthesis essential energy production Co-factor (Coenzyme Q10). The aim from this research includes study the effect of statin drugs (Simvastatin and Atorvastatin) on the Coenzyme Q10 using differential pulse polarographic technique at a dropping mercury electrode (DME) and in a mixture of [4:1] methanol-phosphate buffer of pH7.0 as supporting an electrolyte. Prior to this, the behaviors of Simvastatin, Atorvastatin and Coenzyme Q10 were studied separately in their solvents. The half-wave potential (E1/2) of Co Q10 were -0.31volt and -1.37Volt, -1.33 Volt for simvastatin and atorvastatin respectively. A mixture of Co

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Publication Date
Mon May 25 2020
Journal Name
International Journal Of Psychosocial Rehabilitation
Training for Anaerobic Differential Threshold Stand and its Impact on Lactic Acid Concentration and LDH Enzyme and VO2MaX and Cortisol Hormone for Free 400 m men-runners
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The study aimed at designing a training program by using training for the anaerobic differential threshold stand and the effects of those trainings on the variables of (Concentration of Lactic Acid and LDH Enzyme, VO2 MaX and Cortisol Hormone). The Researchers used the experimental program with one-group style. Also, they used a sample with (8) men-players in a (free 400 m men-runners) and they used many instruments and procedures, most notably the training-program prepared for 10 weeks and for 3 training units weekly, (70-90 min) for each unit. They used the training intensity from 85-100% of the player's ability. After finishing the training program and doing some pre-tests and post-tests then statistically checking the results, the resea

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Publication Date
Fri Jun 01 2018
Journal Name
Kerbala Journal Of Medicine
Polymerase Chain Reaction Testing in Comparison to Culture of Cerebrospinal Fluid for Diagnosis of Bacterial Meningitis in Children
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Publication Date
Sat Dec 03 2022
Journal Name
Tikrit Journal Of Pure Science
A Pixel Based Method for Image Compression
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The basic solution to overcome difficult issues related to huge size of digital images is to recruited image compression techniques to reduce images size for efficient storage and fast transmission. In this paper, a new scheme of pixel base technique is proposed for grayscale image compression that implicitly utilize hybrid techniques of spatial modelling base technique of minimum residual along with transformed technique of Discrete Wavelet Transform (DWT) that also impels mixed between lossless and lossy techniques to ensure highly performance in terms of compression ratio and quality. The proposed technique has been applied on a set of standard test images and the results obtained are significantly encourage compared with Joint P

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Publication Date
Sat Dec 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
New Proposed Method For Web Services Security
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TI1e Web service securi ty challenge is to understand  and  assess the risk  involved  in securing  a web-based  service  today, based on our existing security technology, and at the same time tmck emerging standards and  understand  how they will be used  to offset the risk in

new web services. Any  security model must  i llustrate  how data  can

now  through   an  application   and   network   topology  to  meet  the

requirements  defined  by the busi ness  wi thout exposing  the data  to undue  risk.  In this paper  we propose &n

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Publication Date
Sat Jan 01 2011
Journal Name
Journal Of Engineering
FINITE ELEMENT METHOD FOR INCOMPRESSIBLE VISCOELASTIC MATERIALS
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A numerical method (F.E.)was derived for incompressible viscoelastic materials, the aging and
environmental phenomena especially the temperature effect was considered in this method. A
treatment of incompressibility was made for all permissible values of poisons ratio. A
mechanical model represents the incompressible viscoelastic materials and so the properties can
be derived using the Laplace transformations technique .A comparison was made with the other
methods interested with viscoelastic materials by applying the method on a cylinder of viscoelastic material surrounding by a steel casing and subjected to a constant internal pressure, as well as a comparison with another viscoelastic method and for Asphalt Concrete pro

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Publication Date
Mon Jun 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Suggested method for modifying the site parameter
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     Estimating multivariate location and scatter with both affine equivariance and positive break down has always been difficult. Awell-known estimator which satisfies both properties is the Minimum volume Ellipsoid Estimator (MVE) Computing the exact (MVE) is often not feasible, so one usually resorts to an approximate Algorithm. In the regression setup, algorithm for positive-break down estimators like Least Median of squares typically recomputed the intercept at each step, to improve the result. This approach is called intercept adjustment. In this paper we show that a similar technique, called location adjustment, Can be applied to the (MVE). For this purpose we use the Minimum Volume Ball (MVB). In order

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Publication Date
Wed May 01 2019
Journal Name
Journal Of Engineering
Reduced Complexity SLM Method for PAPR Reduction
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In this paper, the computational complexity will be reduced using a revised version of the selected mapping (SLM) algorithm. Where a partial SLM is achieved to reduce the mathematical operations around 50%. Although the peak to average power ratio (PAPR) reduction gain has been slightly degraded, the dramatic reduction in the computational complexity is an outshining achievement. Matlab simulation is used to evaluate the results, where the PAPR result shows the capability of the proposed method.  

 

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Publication Date
Wed May 25 2022
Journal Name
Iraqi Journal Of Science
The Optimal Control Problem for Triple Nonlinear Parabolic Boundary Value Problem with State Vector Constraints
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       In this paper, the classical continuous triple optimal control problem (CCTOCP) for the triple nonlinear parabolic boundary value problem (TNLPBVP) with state vector constraints (SVCs) is studied.  The solvability theorem for the classical continuous triple optimal control vector CCTOCV with the SVCs is stated and proved. This is done under suitable conditions. The mathematical formulation of the adjoint triple boundary value problem (ATHBVP) associated with TNLPBVP is discovered. The Fréchet derivative of the Hamiltonian" is derived.  Under suitable conditions, theorems of necessary  and sufficient conditions for the optimality of the TNLPBVP with the SVCs are stated and proved.    

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