AlKhwarizmi Engineering Journal,
Vol.3, No. 2(2007)
No.

Author Name

Title

Abstract

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1

Dr. Dhafer r. Zaghar

Reduction of the error in the hardware neural network.

Specialized hardware implementations of Artificial Neural Networks (ANNs) can offer faster execution than generalpurpose microprocessors by taking advantage of reusable modules, parallel processes and specialized computational components. Modern highdensity Field Programmable Gate Arrays (FPGAs) offer the required flexibility and fast designtoimplementation time with the possibility of exploiting highly parallel computations like those required by ANNs in hardware.

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2

Dr. Shereen F. AbdAlkarim

Application of Fuzzy Logic in Servo Motor.

In this work the design and application of a fuzzy logic controller to DCservomotor is investigated. The proposed strategy is intended to improve the performance of the original control system by use of a fuzzy logic controller (FLC) as the motor load changes. Computer simulation demonstrates that FLC is effective in position control of a DCservomotor comparing with conventional one.

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3

Dr. Sattar j. Habbeb

Investigation of heat transfer phenomena and flow behavior around electronic chip.

Computational study of threedimensional laminar and turbulent flows around electronic chip (heat source) located on a printed circuit board are presented. Computational field involves the solution of elliptic partial differential equations for conservation of mass, momentum, energy, turbulent energy, and its dissipation rate in finite volume form. The kε turbulent model was used with the wall function concept near the walls to treat of turbulence effects. The SIMPLE algorithm was selected in this work. The chip is cooled by an external flow of air.

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4

Assist. Prof. Dr. Nabeel K.ALsahib,
Malik M. Ali

Effect of the Mechanical and Thermal Stresses of Rotating Blades.

Rotating blades are the important parts in gas turbines. Hence, an accurate mathematical estimation (F.E.M) of the stresses and deformations characteristics was required in the design applications to avoid failure. In recent year’s there are researchers interest in the effect of temperature on solid bodies has greatly increased, The main of this study investigated the thermal and rotational effects.

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5

Dr. Aziz AlAlawi
Dr. Albert E. Yousif
Muneer A. H.

An Investigation into the Behavior of Disc BlakeWear.

A real method of predication brake pad wear ,could lead to substantiol economies of time and money. This paper describes how such a procedure has been used and gives the results to establish is reliability by comparing the predicted wear with that which actually occurs in an existing service. The experimental work was carried out on three different commercial samples ,tested under different operation conditions (speed,load,time...etc)using a test ring especially modified for this purpose. Abrasive wear is mainly studied , since it is the type of wear that takes place in such arrangements. Samples wear tested in presences of sand or mud between the mating surfaces under different operational conditions of speed, load and braking time . Mechanical properties of the pad material samples (hardness, young,s modulus and collapse load under pure bending condition )wear established . The thermal conductivity and surface roughness of the pad material wear also found in order to enable comparison between the surface condition before and after testing. Sliding velocity had a small effect on the wear rate but it had great effect on friction coefficient. Wear rate was affected mainly by the surface temperature which causing a reduction friction coefficient and increasing the wear rate. Surface roughness had almost no effect on the wear rate since it was proved experimentally ,that the surface becomes softer during operation .mechanical properties of the pad material had fluctuating effect on wear rate. The existence of solid particles between pad and disc increasing wear rate and friction coefficient while the mud caused a reduction in wear rate of the pad surface since it acts as a lubricant absorbing the surface heat generated during sliding the area of contact between pad and disc. wear rate obtained experimentally agreed fairly well that found from empirically obtained equations 
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6

Dr. Khalid Farhod Chasib AlJiboury

Correlation for fitting multicomponent vaporliquid equilibria data and prediction of azeotropic behavior.

Correlation equations for expressing the boiling temperature as direct function of liquid composition have been tested successfully and applied for predicting azeotropic behavior of multicomponent mixtures and the kind of azeotrope (minimum, maximum and saddle type) using modified correlation of GibbsKonovalov theorem. Also, the binary and ternary azeotropic point have been detected experimentally using graphical determination on the basis of experimental binary and ternary vaporliquid equilibrium data.

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