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Free Vibration Analysis for Dynamic Stiffness Degradation of Cracked Cantilever Plate
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In the present work a dynamic analysis technique have been developed to investigate and characterize the quantity of elastic module degradation of cracked cantilever plates due to presence of a defect such as surface of internal crack under free vibration. A new generalized technique represents the first step in developing a health monitoring system, the effects of such defects on the modal frequencies has been the main key quantifying the elasticity modulii due to presence any type of un-visible defect. In this paper the finite element method has been used to determine the free vibration characteristics for cracked cantilever plate (internal flaws), this present work achieved by different position of crack. Stiffness reduction in term of elastic material properties is analyzed through a parametric study of crack density factor. Results are given for Young’s modulus and shear modulus variation with respects the vibrational characteristics.                        

 

 

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Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Use Principal Component Analysis Technique to Dimensionality Reduction to Multi Source
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This paper tackles with principal component analysis method (PCA ) to dimensionality reduction in the case of linear combinations to digital image processing and analysis. The PCA is statistical technique that shrinkages a multivariate data set consisting of inter-correlated variables into a data set consisting of variables that are uncorrelated linear combination, while ensuring the least possible loss of useful information. This method was applied to a group of satellite images of a certain area in the province of Basra, which represents the mouth of the Tigris and Euphrates rivers in the Shatt al-Arab in the province of Basra.

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Publication Date
Fri Mar 17 2017
Journal Name
Elixir Mech. Engg. 109 (2017) 47879-47881, Www. Elixirpublishers. Com …‏
Effect of Cutting Angle for a Locally Assembling Motorized Vibration Cutter on Some Operational Characteristics Used for Date Palm Fronds Cutting
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Publication Date
Wed Jan 30 2019
Journal Name
Journal Of The College Of Education For Women
Identify indicators of climate change through the analysis of the amount of rain in Iraq
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United nation determined many basic climatic effects which affect the crust of Earth.
And the most important one is the climatic change and its effect on environmental, economic,
social, and political effects. So, the amount of rain which is considered as one of climatic
changes in Iraq should be studied.So, this research explains the factors which affect rain, its
overall average, the variation in the amounts of rain, the amount of yearly rain and variation
in both yearly and monthly rains by using standard variation and yearly fluctuation.As a
result, it is concluded that the number of rainy days doesn't mean an increase in rains amount.
And there's variation in rains amount in all study areas which is contrastive

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
A GENERAL VELOCITY PROFILE FOR A LAMINAR BOUNDARY LAYER OVER FLAT PLATE WITH ZERO INCIDENCE
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A general velocity profile for a laminar flow over a flat plate with zero incidence is obtained by employing a new boundary condition to the other available boundary conditions. The general velocity profile is mathematically simple and nearest to the exact solution. Also other related values, boundary layer thickness, displacement thickness, momentum thickness and coefficient of friction are nearest to the exact solution compared with other corresponding values for other researchers.

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Publication Date
Wed May 10 2023
Journal Name
Journal Of Engineering
Damage Detection and Assessment of Stiffness and Mass Matrices in Curved Simply Supported Beam Using Genetic Algorithm
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In this study, a genetic algorithm (GA) is used to detect damage in curved beam model, stiffness as well as mass matrices of the curved beam elements is formulated using Hamilton's principle. Each node of the curved beam element possesses seven degrees of freedom including the warping degree of freedom. The curved beam element had been derived based on the Kang and Yoo’s thin-walled curved beam theory. The identification of damage is formulated as an optimization problem, binary and continuous genetic algorithms
(BGA, CGA) are used to detect and locate the damage using two objective functions (change in natural frequencies, Modal Assurance Criterion MAC). The results show the objective function based on change in natural frequency i

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Publication Date
Fri Aug 13 2021
Journal Name
Journal Européen Des Systèmes Automatisés
Proxy-based sliding mode vibration control with an adaptive approximation compensator for euler-bernoulli smart beams
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Proxy-based sliding mode control PSMC is an improved version of PID control that combines the features of PID and sliding mode control SMC with continuously dynamic behaviour. However, the stability of the control architecture maybe not well addressed. Consequently, this work is focused on modification of the original version of the proxy-based sliding mode control PSMC by adding an adaptive approximation compensator AAC term for vibration control of an Euler-Bernoulli beam. The role of the AAC term is to compensate for unmodelled dynamics and make the stability proof more easily. The stability of the proposed control algorithm is systematically proved using Lyapunov theory. Multi-modal equation of motion is derived using the Galerkin metho

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Simulation and experimental study of Pin-Plate DC discharge plasma technique
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The present work intends to study of dc glow discharge were generated between pin (cathode) and a plate (anode) in Ar gas is performed using COMSOL were used to study electric field distribution along the axis of the discharge and also the distribution of electron density and electron temperature at constant pressure (P=.0.0mbar) and inter electrode distance (d=4 cm) at different applied voltage for both pin cathode system and plate anode and comparison with experimental results.

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
THE EFFECT OF SPACE VOLUME ON FREE CONVECTION HEAT TRANSFER FOR ONGITUDINAL FINNED CYLINDER WITH DIFFERENT SLOPE NGLES
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This study deals with free convection heat transfer for the outer surface of two
cylinders of the shape of (Triangular & Rectangular fined cylinders with 8-fins),
putted into two different spaces; small one with dimension of (Length=1.2m,
height=1m, width=0.9m) and large one with dimension of (Length=3.6m, height =3m,
width=2.7m). The experimental work was conducted with air as a heat transport
medium. These cylinders were fixed at different slope angles (0o, 30o, 60o and 90o)
.The heat fluxes were (279, 1012, 1958, 3005, 4419) W/m2, where heat transferred by
convection and radiation. In large space, the results show that the heat transfer from
the triangular finned cylinder is maximum at a slope angle equals

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Publication Date
Sun Nov 26 2017
Journal Name
Journal Of Engineering
Numerical Study of Heat Transfer Enhancement for a Flat Plate Solar Collector by Adding Metal Foam Blocks
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Numerical study has been conducted to investigate the thermal performance enhancement of flat plate solar water collector by integrating the solar collector with metal foam blocks.The flow is assumed to be steady, incompressible and two dimensional in an inclined channel. The channel is provided with eight foam blocks manufactured form copper. The Brinkman-Forchheimer extended Darcy model is utilized to simulate the flow in the porous medium and the Navier-Stokes equation in the fluid region. The energy equation is used with local thermal equilibrium (LTE) assumption to simulate the thermofield inside the porous medium. The current investigation covers a range of solar radiation intensity at 09:00 AM, 12:00 PM, and 04:00

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Publication Date
Thu Jan 31 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Analysis the Expected Profit By the Relation Between the Sustainable growth and Actual growth: Apply Study for Iraq Stock Exchange
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The research aims to analysis the future profits of companies listed on the Iraq Stock Exchange through analyzing the relationship between Actual Growth and Sustainable Growth, The study was applied to the sample of companies included in the Iraq Stock Exchange for the period (2010- 2014), The Internal Growth Rate has been used as a measure for the Actual Return Rate but the Sustainable Growth Rate has been measured under the Rose model, The research showed group of conclusions, the most important are:1. From the analysis of sustainable growth for the banks sample and the variables involved in its measure shows that investment in the investors amounts have achieved a significant return, which demonstrates the company's efficiency at gene

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