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Numerical Simulation of 3D- Flow Structure and Heat Transfer for Longitudinal Riblet Upstream of Leading Edge Endwall Junction of Nozzle Guide Vane
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The simulation have been made for  3D flow structure and heat  transfer with and without

longitudinal riblet upstream of leading edge vane endwall junction of first stage nozzle guide vane .The research explores concept of weakening the secondary flows and reducing their harmful effects.Numerical investigation involved examination of the secondary flows ,velocity and heat transfer rates by solving the governing equations (continuity, Navier -stokes and energy equations ) using the known package FLUENT version (12.1).The governing equations were solved for three dimentional, turbulent flowe, incompressible with an appropriate turbulent model (k-ω,SST) .The numerical solution was carried out for 25 models of V-groove riblet with wide ranges of height (h) and space (s). The results indicated that, the riblet endwall junction was a powerful tool for controlling the flow structure, reducing secondary flow formation,and elimination the effect of heat transfer at leading edg and passage . The drag reduction produced by riblet was proportional with their height and space. V-groove riblet with dimension of (h=1.35mm and s=2.26mm) was found to be the most effective in reduction of drag (2.7%) and heat transfer (21%) so it was selected as an optimum dimension of riblet model. The results also showed that the drag reduction produced by riblet was proportional to their size. The riblet model had a great effect in elimination spanwise ,pitchwise velocities ,but strength the streamwise velocity .At leading edge ,the effect of secondary flow was extended up to 23% from span height and 35% upstream leading edge .The riblet model caused an increase in momentom at a region very close to leading edge and to move stagnation point very close to the leading edge.

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Publication Date
Sun Mar 01 2020
Journal Name
Gazi University Journal Of Science
Reliable Iterative Methods for Solving the Falkner-Skan Equation
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Publication Date
Tue Jan 01 2008
Journal Name
2008 15th Asia-pacific Software Engineering Conference
G2Way A Backtracking Strategy for Pairwise Test Data Generation
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Publication Date
Sun Jan 01 2023
Journal Name
Computers, Materials & Continua
An Optimal Algorithm for Resource Allocation in D2D Communication
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Publication Date
Thu Mar 30 2023
Journal Name
Iraqi Journal Of Science
Constructing a Digital Certificate Authentication System for Classified Documents
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             In this paper, we introduce a new digital authentication certification system to keep the classified documents' information safe. The proposed system is a steganography system divided into two subsystems, the first subsystem is responsible for embedding the information about the person, and it works in the main foundation that issues the documents, while the second subsystem is found in the beneficiary directorates to extract the true information of the person.

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Publication Date
Mon Nov 01 2010
Journal Name
Iraqi Journal Of Physics
Night Vision monitor for IR laser spot size Identification
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The aim of this research is to design and construct a
semiconductor laser range finder operating in the near infrared range
for ranging and designation. The main part of the range finder is the
transmitter which is a semiconductor laser type GaAs of wavelength
0.904 μm with a beam expander and the receiver; a silicon pin
detector biased to approve the fast response time with it's collecting
optics. The transmitters pulse width was 200ns at a threshold current
of 10 Ampere and maximum operating current of 38 Ampere. The
repetition rate was set at 660Hz and the maximum operating output
power was around 1 watt. The divergence of the beam was 0.268o
the efficiency of the laser was 0.03% at a duty cycle of 1.32x

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Publication Date
Wed Jul 06 2022
Journal Name
Journal Of Al-qadisiyah For Computer Science And Mathematics
Pixel Based Techniques for Gray Image Compression: A review
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Currently, with the huge increase in modern communication and network applications, the speed of transformation and storing data in compact forms are pressing issues. Daily an enormous amount of images are stored and shared among people every moment, especially in the social media realm, but unfortunately, even with these marvelous applications, the limited size of sent data is still the main restriction's, where essentially all these applications utilized the well-known Joint Photographic Experts Group (JPEG) standard techniques, in the same way, the need for construction of universally accepted standard compression systems urgently required to play a key role in the immense revolution. This review is concerned with Different

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Publication Date
Mon Dec 03 2018
Journal Name
Journal Of Engineering
Error Investigation for Free Form Surfaces in Bezier Techniques
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Surface modeling utilizing Bezier technique is one of the more important tool in computer aided geometric design (CAD). The aim of this work is to design and implement multi-patches Bezier free-form surface. The technique has an effective contribution in technology domains and in ships, aircrafts, and cars industry, moreover for its wide utilization in making the molds. This work is includes the synthesis of these patches in a method that is allow the participation of these control point for the merge of the patches, and the confluence of patches at similar degree sides due to degree variation per patch.  The model has been implemented to represent the surface. The interior data of the desired surfaces designed by M

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
Using Semi-Analytic Technique for Solving Lane Emden Equations
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This paper propose the semi - analytic technique using two point osculatory interpolation to construct polynomial solution for solving some well-known classes of Lane-Emden type equations which are linear ordinary differential equations, and disusse the behavior of the solution in the neighborhood of the singular points along with its numerical approximation. Many examples are presented to demonstrate the applicability and efficiency of the methods. Finally , we discuss behavior of the solution in the neighborhood of the singularity point which appears to perform satisfactorily for singular problems.

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Publication Date
Tue Jan 18 2022
Journal Name
Iraqi Journal Of Science
Modified Bees Swarm Optimization Algorithm for Association Rules Mining
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Mining association rules is a popular and well-studied method of data mining tasks whose primary aim is the discovers of the correlation among sets of items in the transactional databases. However, generating high- quality association rules in a reasonable time from a given database has been considered as an important and challenging problem, especially with the fast increasing in database's size. Many algorithms for association rules mining have been already proposed with promosing results. In this paper, a new association rules mining algorithm based on Bees Swarm Optimization metaheuristic named Modified Bees Swarm Optimization for Association Rules Mining (MBSO-ARM) algorithm is proposed. Results show that the proposed algorithm can

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Publication Date
Wed Jun 26 2019
Journal Name
Iraqi Journal Of Science
Comprehensive Processing for Arabic Texts to Extract Their Roots
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Arabic language is a highly inflectional language where a single word can have different forms using a single root with different interpretations. Arabic does not have a standard way to find roots, the reasons for having inflectional language: suffix, prefix and infix Vowels, which built in complex processes. That is why, words require good processing for information retrieval solutions, until now, and there has been no standard approach to attaining the fully proper root. The applications on Arabic words show around 99% are derived from a combination of bilateral, Trilateral and quad lateral roots.
Processing word- stemming levels in order to extract a root is the process of removing all additional affixes. In case the process of mat

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