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joe-2040
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 Nov 12 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
New Taxa For Trachomitum Woodson (Apocynaceae) in Iraq
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The present study includes a morphological investigation to

the plant specimens of the genus Trachomitum which assembling by one species in Iraq it is T  venetum (L.) Woodson. The specimens in

the Iraqi herbaria and that which is collected for the first time from new locations. After a detail  and specific investigation for all the

characteristic features, and according to the obvious variations between different parts of the plants we can identify the specimens of the   species  .T venetum   into  three  subspecies  which  are  subsp. armenum, subsp. scabrum and subsp. sarmatiense .

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Publication Date
Sat Dec 30 2017
Journal Name
International Journal Of Science And Research (ijsr)
Color-based for tree yield fruits image counting
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Identifying the total number of fruits on trees has long been of interest in agricultural crop estimation work. Yield prediction of fruits in practical environment is one of the hard and significant tasks to obtain better results in crop management system to achieve more productivity with regard to moderate cost. Utilized color vision in machine vision system to identify citrus fruits, and estimated yield information of the citrus grove in-real time. Fruit recognition algorithms based on color features to estimate the number of fruit. In the current research work, some low complexity and efficient image analysis approach was proposed to count yield fruits image in the natural scene. Semi automatic segmentation and yield calculation of fruit

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Publication Date
Wed Jan 23 2019
Journal Name
Natural Resources Research
Tigris River Sediments as Abrasive for Polishing Marble
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Publication Date
Wed May 12 2021
Journal Name
Annals Of The Romanian Society For Cell Biology
Hashimoto's Thyroiditis Increases Risk for Differentiated Thyroid Carcinoma
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Background: Hashimoto's thyroiditis has been found to coexist with differentiated thyroid cancer in surgical specimens, but an association between the two conditions has been discounted by the medical literature. So, we performed this research to determine any potential relationship between Hashimoto's thyroiditis and the risk of developing differentiated thyroid cancer in clinical status. we assessed the related clinical factors linking these conditions, especially serum thyroid-stimulating hormone concentration, family history of thyroid disease, gender& young age group. Aim of study: to determine that hashimoto’s thyroiditis increases risk for differentiated thyroid carcinoma. Patients and method: This study is a Cross-sectiona

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Publication Date
Thu Aug 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Some NONPARAMETRIC ESTIMATORS FOR RIGHT CENSORED SURVIVAL DATA
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The using of the parametric models and the subsequent estimation methods require the presence of many of the primary conditions to be met by those models to represent the population under study adequately, these prompting researchers to search for more flexible parametric models and these models were nonparametric, many researchers, are interested in the study of the function of permanence and its estimation methods, one of these non-parametric methods.

For work of purpose statistical inference parameters around the statistical distribution for life times which censored data , on the experimental section of this thesis has been the comparison of non-parametric methods of permanence function, the existence

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Publication Date
Thu Jul 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Direct Method for Variational Problems Using Boubaker Wavelets
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The wavelets have many applications in engineering and the sciences, especially mathematics. Recently, in 2021, the wavelet Boubaker (WB) polynomials were used for the first time to study their properties and applications in detail. They were also utilized for solving the Lane-Emden equation. The aim of this paper is to show the truncated Wavelet Boubaker polynomials for solving variation problems. In this research, the direct method using wavelets Boubaker was presented for solving variational problems. The method reduces the problem into a set of linear algebraic equations. The fundamental idea of this method for solving variation problems is to convert the problem of a function into one that involves a finite number of variables. Diff

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Publication Date
Sun Dec 07 2008
Journal Name
Baghdad Science Journal
Optimal Color Model for Information Hidingin Color Images
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In present work the effort has been put in finding the most suitable color model for the application of information hiding in color images. We test the most commonly used color models; RGB, YIQ, YUV, YCbCr1 and YCbCr2. The same procedures of embedding, detection and evaluation were applied to find which color model is most appropriate for information hiding. The new in this work, we take into consideration the value of errors that generated during transformations among color models. The results show YUV and YIQ color models are the best for information hiding in color images.

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Publication Date
Tue Aug 17 2021
Journal Name
Materials
Recycled Concrete Aggregate for Medium-Quality Structural Concrete
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This paper reports an evaluation of the properties of medium-quality concrete incorporating recycled coarse aggregate (RCA). Concrete specimens were prepared with various percentages of the RCA (25%, 50%, 75%, and 100%). The workability, mechanical properties, and durability in terms of abrasion of cured concrete were examined at different ages. The results reveal insignificant differences between the recycled concrete (RC) and reference concrete in terms of the mechanical and durability-related measurements. Meanwhile, the workability of the RC reduced vastly since the replacement of the RCA reached 75% and 100%. The ultrasound pulse velocity (UPV) results greatly depend on the porosity of concrete and the RC exhibited higher poros

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Publication Date
Sun Nov 01 2020
Journal Name
Journal Of Physics: Conference Series
Purification Techniques for Cheap Multi –Walled Carbon Nanotubes
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Abstract<p>Multi-walled carbon nanotubes from cheap tubs company MWCNT-CP were purified by alcohol \ H2O2 \ separation funnel which is simple, easy and scalable techniques. The steps of purification were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy SEM with energy dispersive of X-ray spectroscopy EDX and surface area measurements. The technique was succeeded to remove most the trace element from MWCNT-CP which causing increase the surface area. The ratios of impurities were reduced to less 0.6% after treatment by three steps with losing less than 5% from MWCNT-CP.</p>
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Publication Date
Wed Jun 07 2023
Journal Name
Journal Of Educational And Psychological Researches
Omani Second-Cycle Students’ Motivations for Electronic Games
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The current study aims to investigate the second cycle students’ motives for using electronic games in Oman. The sample consisted of (570) students, (346 males and 224 females). The participants completed an open-ended question which was analyzed based on ground theory. The results showed that (46.820%) of the males and (77.678) of the females played electronic games for pleasure, entertainment, and fun. This first category of motivation got the highest percentage of frequency (58.947%). The motive to become a hacker, a popular YouTuber got the lowest percentage (2.280%). Other students’ motives toward playing electronic games included: filling the leisure time, overcoming boredom, feeling adventures, getting science fiction and chal

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