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Identification of Time-Wise Thermal Diffusivity, Advection Velocity on the Free-Boundary Inverse Coefficient Problem
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This paper is concerned with finding solutions to free-boundary inverse coefficient problems. Mathematically, we handle a one-dimensional non-homogeneous heat equation subject to initial and boundary conditions as well as non-localized integral observations of zeroth and first-order heat momentum. The direct problem is solved for the temperature distribution and the non-localized integral measurements using the Crank–Nicolson finite difference method. The inverse problem is solved by simultaneously finding the temperature distribution, the time-dependent free-boundary function indicating the location of the moving interface, and the time-wise thermal diffusivity or advection velocities. We reformulate the inverse problem as a non-linear optimization problem and use the lsqnonlin non-linear least-square solver from the MATLAB optimization toolbox. Through examples and discussions, we determine the optimal values of the regulation parameters to ensure accurate, convergent, and stable reconstructions. The direct problem is well-posed, and the Crank–Nicolson method provides accurate solutions with relative errors below 0.006% when the discretization elements are M=N=80. The accuracy of the forward solutions helps to obtain sensible solutions for the inverse problem. Although the inverse problem is ill-posed, we determine the optimal regularization parameter values to obtain satisfactory solutions. We also investigate the existence of inverse solutions to the considered problems and verify their uniqueness based on established definitions and theorems.

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Publication Date
Tue Dec 01 2020
Journal Name
2020 5th Ieee International Conference On Recent Advances And Innovations In Engineering (icraie)
The New Way of Estimating the PCB's Lifetime of Fatigue using the Principle of Linear Accumulated Damage in Various Boundary Condition
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Publication Date
Mon Jan 01 2018
Journal Name
Al–bahith Al–a'alami
Research Problem: Concept, Formation and Characteristics
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This paper focuses on the most important element of scientific research: the research problem which is confined to the concept of concern or concern surrounding the researcher about any event or phenomenon or issue paper and need to be studied and addressed in order to find solutions for them, to influence the most scientific research steps from asking questions and formulating hypotheses, to employ suitable methods and tools to choose the research and sample community, to employ measurement and analysis tools. This problem calls for a great effort by the researcher intellectually or materially to develop solutions.

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Publication Date
Fri Apr 01 2022
Journal Name
Baghdad Science Journal
Attacking Jacobian Problem Using Resultant Theory
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     This paper introduces a relation between resultant and the Jacobian determinant
by generalizing Sakkalis theorem from two polynomials in two variables to the case of (n) polynomials in (n) variables. This leads us to study the results of the type:  ,            and use this relation to attack the Jacobian problem. The last section shows our contribution to proving the conjecture.

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Publication Date
Wed Mar 01 2023
Journal Name
Journal Of Engineering
The Roughness Coefficient in Euphrates River Reach between Haditha Dam to Ramadi Barrage
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Accurate computation of the roughness coefficient is important in the studies of open channel flow. To measure and identify the hydraulic characteristics of the flow system, the model simulation is necessary to study and get the results of the hydraulic properties to specify Manning coefficient of the Euphrates River. In this study, the reach is extended along the Euphrates River from Haditha Dam to Ramadi Barrage with a distance of 169km. The HEC-RAS model was implemented to simulate the flow within the study reach. The geometry of the river was represented by more than two hundred cross-sections surveyed in 2013 and 2021. The model was calibrated using some observed discharges at the Heet gage station for records of th

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Publication Date
Sun Jun 05 2011
Journal Name
Baghdad Science Journal
Correlation between Paris function parameters to crack velocity for Alumina ceramics
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The question about the existence of correlation between the parameters A and m of the Paris function is re-examined theoretically for brittle material such as alumina ceramic (Al2O3) with different grain size. Investigation about existence of the exponential function which fit a good approximation to the majority of experimental data of crack velocity versus stress intensity factor diagram. The rate theory of crack growth was applied for data of alumina ceramics samples in region I and making use of the values of the exponential function parameters the crack growth rate theory parameters were estimated.

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Publication Date
Wed Mar 01 2017
Journal Name
Archive Of Mechanical Engineering
Using the Lid-Driven Cavity Flow to Validate Moment-Based Boundary Conditions for the Lattice Boltzmann Equation
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Abstract<p>The accuracy of the Moment Method for imposing no-slip boundary conditions in the lattice Boltzmann algorithm is investigated numerically using lid-driven cavity flow. Boundary conditions are imposed directly upon the hydrodynamic moments of the lattice Boltzmann equations, rather than the distribution functions, to ensure the constraints are satisfied precisely at grid points. Both single and multiple relaxation time models are applied. The results are in excellent agreement with data obtained from state-of-the-art numerical methods and are shown to converge with second order accuracy in grid spacing.</p>
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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Shot Peening Time Effect on Corrosion Behaviors of Al Alloy 2024-T3
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In this study many specimen s were prepared from 2024-T3 Aluminum alloy for corrosion test by the dimensions of (15*15*3) mm according to ASTM G71-31 and then subjected to shot peening process at different time (15, 30, 45) minutes using steel ball having a diameter of 2.75 mm and Rockwell Hardness of 55RC to induce compressive residual stress which were measured using X-Ray diffraction method, surface roughness and   hardness were tested before and after peening. Electrochemical corrosion test by Tafel extrapolation method was carried out in an environment of 3 .5% NaCl solutions (sea water) where Corrosion rate calculated using Tafle equation.

The obtained results show a favorable influence of SP treatment

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Publication Date
Thu Jun 30 2011
Journal Name
Al-khwarizmi Engineering Journal
Characterization of Delamination Effect on Free Vibration of Composite Laminates Plate Using High Order Shear Deformation Theory
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 A dynamic analysis method has been developed to investigate and characterize embedded delamination on the dynamic response of composite laminated structures. A nonlinear finite element model for geometrically large amplitude free vibration intact plate and delamination plate analysis is presented using higher order shear deformation theory where the nonlinearity was introduced  in the Green-Lagrange sense. The governing equation of the vibrated plate were derived using the Variational approach. The effect of different orthotropicity ratio, boundary condition and delamination size on the non-dimenational fundamental frequency and frequency ratios of plate for different stacking sequences are studied. Finally th

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Publication Date
Sun Mar 13 2011
Journal Name
Baghdad Science Journal
Effect of some Organic Pollutants (furfural and toluene) on Biological Aspects of Free- living Ciliate Oxytricha falax
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Samples of Oxytricha falax were collected from Tigris River by 55µ. mesh net. Culturing of O. falax were cultivated in specific conditions (DO 3-5mg/l.; W.Temp. 24±1ºC; pH: 6.8-7.5).The effect of various furfural concentration 0, 20, 40, 80,100 and 124 ppm and toluene concentration 0, 15, 30, 34.2, 34.5 and 35 ppm after two periods of treatment (24 and 48 hr.) on the physiological parameters of O. falax ciliate were observed. This study showed that the lethal concentration of furfural was 124ppm and 80ppm after 24hr. and 48hr. from treatment which killed all the individual community respectively. Furthermore the treatment of O. falax individuals with different concentrations of toluene indicated that 34.5 ppm of it caused disappearance o

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Publication Date
Sun Dec 16 2018
Journal Name
Al-academy
Deconstruction the Theatrical Time in the Expressionist Doctrine
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Time affects all elements of the intellectual scene or the theatrical scene. It came along with the theatrical doctrines according to the conditions of those doctrines and their conceptual ideas or the method of their mechanisms in the application. While it is classically or realistically integrated, we see it in the expressionist doctrine inconsistent and its inconsistency makes it responsive for the deconstruction strategy. Hence the researcher entitled his study (deconstruction the theatrical time in the expressionist doctrine) so that deconstruction would be a field for his study.   The study starts with an introduction presenting the research problem, importance and objective. The theoretical framework consisted of three s

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