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Mixed Implicit Galerkin – Frank Wolf, Gradient and Gradient Projection Methods for Solving Classical Optimal Control Problem Governed by Variable Coefficients, Linear Hyperbolic, Boundary Value Problem
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This paper deals with testing a numerical solution for the discrete classical optimal control problem governed by a linear hyperbolic boundary value problem with variable coefficients. When the discrete classical control is fixed, the proof of the existence and uniqueness theorem for the discrete solution of the discrete weak form is achieved. The existence theorem for the discrete classical optimal control and the necessary conditions for optimality of the problem are proved under suitable assumptions. The discrete classical optimal control problem (DCOCP) is solved by using the mixed Galerkin finite element method to find the solution of the discrete weak form (discrete state). Also, it is used to find the solution for the discrete adjoint weak form (discrete adjoint) with the Gradient Projection method (GPM) , the Gradient method (GM), or the Frank Wolfe method (FWM) to the DCOCP. Within each of these three methods, the Armijo step option (ARSO) or the optimal step option (OPSO) is used to improve (to accelerate the step) the solution of the discrete classical control problem. Finally, some illustrative numerical examples for the considered discrete control problem are provided. The results show that the GPM with ARSO method is better than GM or FWM with ARSO methods. On the other hand, the results show that the GPM and GM with OPSO methods are better than the FWM with the OPSO method.

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Publication Date
Tue May 30 2023
Journal Name
Iraqi Journal Of Science
mRNA Approach Image Encryption Using LUC Algorithm
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      Bioinformatics is one of the computer science and biology sub-subjects concerned with the processes applied to biological data, such as gathering, processing, storing, and analyzing it. Biological data (ribonucleic acid (RNA), deoxyribonucleic acid (DNA), and protein sequences) has many applications and uses in many fields (data security, data segmentation, feature extraction, etc.). DNA sequences are used in the cryptography field, using the properties of biomolecules as the carriers of the data. Messenger RNA (mRNA) is a single strand used to make proteins containing genetic information. The information recorded from DNA also carries messages from DNA to ribosomes in the cytosol. In this paper, a new encryption technique bas

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Publication Date
Thu Mar 01 2018
Journal Name
Journal Of Engineering
Numerical Simulation of Thermal-Hydrodynamic Behavior within Solar Air Collector
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Solar collectors, in general, are utilized to convert the solar energy into heat energy, where it is employed to generate electricity. The non-concentrating solar collector with a circular shape was adopted in the present study. Ambient air is heated under a translucent roof where buoyant air is drawn from outside periphery towards the collector center (tower base). The present study is aimed to predict and visualize the thermal-hydrodynamic behavior for airflow under inclined roof of the solar air collector, SAC. Three-dimensional of the SAC model using the re-normalization group, RNG, k−ε turbulence viscus model is simulated. The simulation was carried out by using ANSYS-FLUENT 14.5. The simulation

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Publication Date
Fri Apr 01 2022
Journal Name
Journal Of Engineering
Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins
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Natural convection in an annular space provided with metal foam fins attached to the inner cylinder is studied numerically. The metal foam fins made of copper were inserted in different axial sections with three fins in each section. The temperature of the inner cylinder is kept constant while the annular outer surface is adiabatic. The thickness effect of the inner pipe wall was considered. Naiver Stokes equation with Boussinesq approximation is used for the fluid regime while Brinkman-Forchheimer Darcy model is used for metal foam. In addition, the local thermal non-equilibrium condition in the energy equation of the porous media is presumed. The effect of Rayleigh numb

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Publication Date
Sat Oct 30 2021
Journal Name
Iraqi Journal Of Science
Theoretical Investigation of the Effects of some Geometrical Parameters on the Performance of Wire-Plate Electrostatic Precipitator
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     Some geometric parameters affecting the performance of a wire-plate electrostatic precipitator (ESP) are investigated theoretically. A numerical model was built to investigate the influence of the discharge wire size, wire separation, collector plates spacing, and roughness factor on the ESP performance. The results show that thinner wires emit higher current than larger ones at the same applied voltage, which would be suitable for low voltage power supply to generate the desired current density at the collecting electrodes. The results also show that, as the discharge electrodes get closer, the corona gets suppressed, resulting in a diminished corona current flow. On the other hand, as the distance between elect

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Physics: Conference Series
Effect of Nickel Substitution On Structural and Electrical Properties of Hg<sub>0.5</sub>Pb<sub>0.5</sub>Ba<sub>2</sub>Ca<sub>2</sub>Cu<sub>3-y</sub>Ni<sub>y</sub>O<sub>8+δ</sub> Superconductor Composite
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Abstract<p>six specimens of the Hg<sub>0.5</sub>Pb<sub>0.5</sub>Ba<sub>2</sub>Ca<sub>2</sub>Cu<sub>3-y</sub> <italic>Ni<sub>y</sub> </italic>O<sub>8+δ</sub> (y=0.2,0.4,0.6,0.8,1.0) superconducting compound were prepared by solid state reaction method, with sintering temperature equal to 1123K for 24 hours. The electrical resistivity was examined by the four probe technique, It was found that all the specimens have metallic behavior and increasing the critical temperature with increasing nickel concentration. The optimum critical temperature T<sub>c</sub> was found equal </p> ... Show More
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Publication Date
Mon Oct 30 2023
Journal Name
Iraqi Journal Of Science
Double Function Random Early Detection (DFRED): A Revised RED-Oriented Algorithm
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     Dropping packets with a linear function between two configured queue thresholds in Random Early Detection (RED) model is incapable of yielding satisfactory network performance. In this article, a new enhanced and effective active queue management algorithm, termed Double Function RED (DFRED in short) is developed to further curtail network delay. Specifically, DFRED algorithm amends the packet dropping probability approach of RED by dividing it into two sub-segments. The first and second partitions utilizes and implements a quadratic and linear increase respectively in the packet dropping probability computation to distinguish between two traffic loads: low and high. The ns-3 simulation performance evaluations clearly indicate t

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Publication Date
Fri Jun 24 2022
Journal Name
Iraqi Journal Of Science
Biological activity of some plants extract against in the survival of rate adult Oryzaephilus surinamensis (Coleopteran Silvanaidae)
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A laboratory study was conducted to evaluate the effect of crud extracts from seven plant species (Nigella sativa, Eugenia caryophylota, Corianderum sativum, Piper nigrum, Peganum hermala, Achillea santolina, Citrullus colocynthis) belong to different families tested as food feeding toxicity against adult of Oryzaephilus surinamensis. The results of the current study showed that hexane extracts from all plants used were more influential in all used concentrations than, the alcoholic extract, and hexane extract of Hanzal was more effective reaching survival rate of adult to 58.3% at concentration of 10% then the plant yarrow and black pepper about 66.2%, and 67.3% respectively, at the same concentration. While the survival rate was approx

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Publication Date
Sun Jul 31 2022
Journal Name
Iraqi Journal Of Science
Association of CTLA-4 Single Nucleotide Polymorphisms with Autoimmune Hypothyroidism in Iraqi Patients
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Genetic and environmental factors are believed to have a key role in the development and pathogenesis of autoimmune thyroid diseases (AITD). This study aimed to investigate the association between two CTLA-4 gene single nucleotide polymorphisms (SNPs) CT60/rs3087243 and CT61/rs11571319 with autoimmune thyroiditis in a sample of Iraqi patients. Seventy-five patients (67 females, 8 males) and eighty-eight subjects (79 females and 9 males) matched in age, gender, and ethnicity as a control group. Thyroid autoantibodies were present in females more than in males with a total positivity of anti-TPO of 92% and anti-TG positivity of
57.3 %. Thyroid evaluation tests including T3, T4, and TSH were abnormal only in patients not receiving L-th

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Publication Date
Thu Jul 01 2021
Journal Name
Journal Of Mechanical Engineering Research And Developments
Numerical Investigation of Natural Convection Heat Transfer in Partially Filled Porous Enclosure Subjected to Constant Heat
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Steady natural convection in a square enclosure with wall length (L= 20 cm) partially filled by saturated porous medium with same fluid (lower layer) and air (upper layer) is investigated. The conceptual study of the achievements of the heat transfer is performed under effects of bottom heating by constant heat flux (q=150,300,450,600W/m2 ) for three heaters size (0.2,0.14,0.07)m with symmetrically cooling with constant temperature on two vertical walls and adiabatic top wall. The relevant filled studied parameters are four different porous medium heights (Hp=0.25L,0.5L, 0.75L, L), Darcey number (Da1) 3.025×10-8 and (Da2) 8.852×10-4 ) and Rayleigh number range (60.354 - 241.41), (1.304×106 – 5.2166×106 ) for Da1 and Da2 cases respecti

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Publication Date
Thu Nov 02 2023
Journal Name
Journal Of Engineering
Numerical Simulation of the Thermal Performance of a Tubular Solar Air Heater
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In this work, a flat-plate solar air heater (FSAH) and a tubular solar air heater (TSAH) were designed and tested numerically. The work investigates the effect of increasing the contact area between the flowing air and the absorber surface of each heater and predicts the expected results before the fabrication of the experimental rig. Three-dimensional two models were designed and simulated by the ANSYS-FLUENT 16 Program. The solar irradiation and ambient air temperature were measured experimentally on December 1st 2022, at the weather conditions of Baghdad City- Iraq, at three air mass flow rates, 0.012 kg/s, 0.032 kg/s, and 0.052 kg/s. The numerical results showed the advantage in the thermal performance of

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