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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 the discrepancy of the results was 17.4906% when the severe nonlinearity is considered.

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Publication Date
Sat Sep 30 2023
Journal Name
Iraqi Journal Of Science
Determination of Alkaloids Constituents in Some Ferns by Using High Performance Liquid Chromatography Technique – Iraq
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    Ferns are considered as important medical herbs. They produce a wide range of secondary metabolites that could be useful in treating different diseases. However, they still remain underexplored in medical aspects in Iraq. Hence, the purpose of this study was to identify alkaloids components in the methanol extracts of four fern species (Asplenium ceterach L., A. scolopendrium L., Cheilanthes pteridioides (Richard) C. Chr. from Malakan region in Erbil Governorate and Equisetum ramosissimum Desf. from Chemi Rezan in Sulaimaniyah Governorate,  of northen Iraq during March - June 2018. The research was conducted by using High performance liquid chromatography (H

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Publication Date
Mon Nov 01 2021
Journal Name
Journal Of Engineering
Stability Improvement of The Iraqi Super Grid (400kV) using High Voltage Direct Current (HVDC) Transmission
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This research analyzes the level of the short circuit effect of the Iraqi super network and decides the suitable location for the High Voltage Direct Current (HVDC) connections in order to obtain the best short circuit reduction of the total currents of the buses in the network. The proposed method depends on choosing the transmission lines for Alternating current (AC) system that suffers from high Short Circuit Levels (SCLs) in order to reduce its impact on the transmission system and on the lines adjacent to it and this after replacing the alternating current (AC) line by direct current (DC) line. In this paper, Power System Simulator for Engineering (PSS/E) is used to model two types of HVDC lines in an effective regi

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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
1-DOF Model for Fluid-Structure-Interaction Vibration Analysis
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In this paper an attempt to provide a single degree of freedom lumped model for fluid structure interaction (FSI) dynamical analysis will be presented. The model can be used to clarify some important concept in the FSI dynamics such as the added mass, added stiffness, added damping, wave coupling ,influence mass coefficient and critical fluid depth . The numerical results of the model show that the natural frequency decrease with the increasing of many parameters related to the structure and the fluid .It is found that the interaction phenomena can become weak or strong depending on the depth of the containing fluid .The damped and un damped free response are plotted in time domain and phase plane for different model parameters It is fou

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Publication Date
Fri Dec 31 2021
Journal Name
Political Sciences Journal
The Effect of the change of Energy Factor on the American-Russian Competition in Europe
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Receipt date:3/13/2021 accepted date:5/26/2021 Publication date:12/31/2021

Creative Commons License This work is licensed under a Creative Commons Attribution 4.0 International License.

energy is one of the strategic resources within international politics, and this is through the existing competition between the international powers on it, and the global powers have begun to rely on interest in new areas, such as import, depending on new projects an

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Publication Date
Tue Sep 11 2018
Journal Name
Iraqi Journal Of Physics
Analytical study of high absorption region of the absorption edge of a-Si:H using nonlinear regression method
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This research is concerned with the re-analysis of optical data (the imaginary part of the dielectric function as a function of photon energy E) of a-Si:H films prepared by Jackson et al. and Ferlauto et al. through using nonlinear regression fitting we estimated the optical energy gap and the deviation from the Tauc model by considering the parameter of energy photon-dependence of the momentum matrix element of the p as a free parameter by assuming that density of states distribution to be a square root function. It is observed for films prepared by Jackson et al. that the value of the parameter p for the photon energy range is is close to the value assumed by the Cody model and the optical gap energy is which is also close to the value

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Publication Date
Thu Jan 06 2022
Journal Name
Kuwait Journal Of Science
AVO analysis for high amplitude anomalies using 2D pre-stack seismic data
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Amplitude variation with offset (AVO) analysis is an 1 efficient tool for hydrocarbon detection and identification of elastic rock properties and fluid types. It has been applied in the present study using reprocessed pre-stack 2D seismic data (1992, Caulerpa) from north-west of the Bonaparte Basin, Australia. The AVO response along the 2D pre-stack seismic data in the Laminaria High NW shelf of Australia was also investigated. Three hypotheses were suggested to investigate the AVO behaviour of the amplitude anomalies in which three different factors; fluid substitution, porosity and thickness (Wedge model) were tested. The AVO models with the synthetic gathers were analysed using log information to find which of these is the

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Publication Date
Sun Feb 24 2019
Journal Name
Iraqi Journal Of Physics
High spatial resolution digital elevation model (DEM) production using different interpolations techniques
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DEMs, thus, simply regular grids of elevation measurements over the land surface.The aim of the present work is to produce high resolution DEM for certain investigated region (i.e. Baghdad University Campus\ college of science). The easting and northing of 90 locations, including the ground-base and buildings of the studied area, have been obtained by field survey using global positioning system (GPS). The image of the investigated area has been extracted from Quick-Bird satellite sensor (with spatial resolution of 0.6 m). It has been geo-referenced and rectified  using 1st order polynomial transformation. many interpolation methods have been used to estimate the elevation such as ordinary Kriging, inverse distance weight

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Publication Date
Tue Jun 12 2007
Journal Name
Iraqi Journal Of Laser
Nonlinear Optical Properties of CdS Thin Film Nanoparticles Using z-Scan Technique
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In the present work, a z-scan technique was used to study the nonlinear optical properties, represented by the nonlinear refractive index and nonlinear absorption coefficients of nanoparticles cadmium sulfide thin film. The sample was prepared by the chemical bath deposition method. Several testing were done including, x-ray, transmission and thickness of thin film. z-Scan experiment was performed at two wavelengths (1064 nm and 532 nm) and different energies. The results showed the effect of self-focusing in the material at higher intensities, which evaluated n2 to be (0.11-0.16) cm2/GW. The effect of two-photon absorption was studied, which evaluated β to be (24-106) cm/GW. In addition, the optical limiting behavior has been studied.

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Publication Date
Tue Mar 30 2021
Journal Name
Baghdad Science Journal
Investigating the Sensitivity Effect of Actuarial Assumptions on Pension Liabilities in Malaysia
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Malaysia will be an ageing population by 2030 as the number of those aged 60 years and above has increased drastically from 6.2 percent in 2000 and is expected to reach 13.6 percent by 2030. There are many challenges that will be faced due to the ageing population, one of which is the increasing cost of pensions in the future. In view of that, it is necessary to investigate the effect of actuarial assumptions on pension liabilities under the perspective of ageing. To estimate the pension liabilities, the Projected Unit Credit method is used in the study and commutation functions are employed in the process. Demographic risk and salary risk have been identified as major risks in analyzing pension liabilities in this study. The sensitivity

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Publication Date
Thu Sep 01 2022
Journal Name
Iaes International Journal Of Robotics And Automation
Implementation of a complex fractional order proportional-integral-derivative controller for a first order plus dead time system
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This paper presents the implementation of a complex fractional order proportional integral derivative (CPID) and a real fractional order PID (RPID) controllers. The analysis and design of both controllers were carried out in a previous work done by the author, where the design specifications were classified into easy (case 1) and hard (case 2) design specifications. The main contribution of this paper is combining CRONE approximation and linear phase CRONE approximation to implement the CPID controller. The designed controllers-RPID and CPID-are implemented to control flowing water with low pressure circuit, which is a first order plus dead time system. Simulation results demonstrate that while the implemented RPID controller fails to stabi

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