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alkej-211
Effect of Bearing Compliance on Thermo-hydrodynamic Lubrication of High Speed Misaligned Journal Bearing Lubricated with Bubbly Oil
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Abstract

In the present work  the effect of bearing compliance on the performance of high speed misaligned journal bearing lined with a compliant PTFE liner lubricated with bubbly oil at high speeds has been studied. The effect of induced oil film temperature due to shearing effect has been implemented. Hydrodynamic effect of the complaint bearing and the influence of aerated oil have been examined by the classical thermohydrodynamic lubrication theory modified to include the effect of oil film turbulence and oil film temperature with suitable models for bubbly oil viscosity and density. The effect of liner elastic deformation has been implemented by using Winkler model. The effects of variable density and specific heat on the most importantbearing parameters such as maximum pressure, maximum temperature, bearing load carrying capacity and power losses have been investigated.The results obtained show that the oil film pressure and load carrying capacity increased for the bearing lubricated with bubbly oil of higher aeration level and smaller size of air bubbles. Including the effect of elastic deformation of the bearing liner reduces the oil film pressure, load carrying capacity and frictional power loss for the misaligned bearing working at the same circumstances

Keywords: Journal bearings, hydrodynamic lubrication, THD, compliant effect, bubbly oil, misalignment effect.

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Publication Date
Wed Nov 02 2022
Journal Name
الجامعة العراقية
الحاجات الارشادية وعلاقتها بالانفتاح على الخبرة
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Publication Date
Sat Nov 02 2024
Journal Name
العلوم القانونية والسياسية
الحروب والصراعات وتداعيتها على الامن الانساني
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تعد الحروب و الصراعات واحدة من اقدم الظواىر التي عرفتها المجتمعات البشرية وان ىذه الظاىرة تجسدت في البداية على مستوى الصراعات الفردية عندما كانت ترتقي الى مستوى الاشتباك وكانت بدائية في وسائلها وادواتها ،وكما ان ظاىرة الحرب بدأت من الاسرة ومن ثم القبيلة والعشيرة وانتهت بالدولة ،اذ ان ظاىرة الحروب بشكلها التقليدي تأخذ شكلا تدميريا بعد ان تتطور ابعادىا القصوى وان حدوثها ىو تضارب مصالح واىداف الاطراف وانها ال

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Publication Date
Mon Dec 01 2008
Journal Name
Political Sciences Journal
تأثير تكوين الشخصية على السلوك السياسي
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تأثير تكوين الشخصية على السلوك السياسي

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Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
أضواء على نشأة مدينة الفلوجة وتطورها
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The study search for the history and the beginning of Faluja city in addition to its growing and developing stages , as well as its planning nature through ottoman era depending on aerial map of Falluja in 1919 as it is the oldest map from Baghdad Real Estate Department, this mentioned map is characterized by the accuracy of the information,

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Publication Date
Sun Feb 25 2024
Journal Name
Baghdad Science Journal
Hybrid CNN-based Recommendation System
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Recommendation systems are now being used to address the problem of excess information in several sectors such as entertainment, social networking, and e-commerce. Although conventional methods to recommendation systems have achieved significant success in providing item suggestions, they still face many challenges, including the cold start problem and data sparsity. Numerous recommendation models have been created in order to address these difficulties. Nevertheless, including user or item-specific information has the potential to enhance the performance of recommendations. The ConvFM model is a novel convolutional neural network architecture that combines the capabilities of deep learning for feature extraction with the effectiveness o

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Publication Date
Sun Jun 20 2021
Journal Name
Baghdad Science Journal
Projective MDS Codes Over GF(27)‎
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MDS code is a linear code that achieves equality in the Singleton bound, and projective MDS (PG-MDS) is MDS code with independents property of any two columns of its generator matrix.   In this paper, elementary methods for modifying a PG-MDS code of dimensions 2, 3, as extending and lengthening, in order to find new incomplete PG-MDS codes have been used over . Also, two complete PG-MDS codes over  of length  and 28 have been found.

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Scopus (7)
Crossref (2)
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Publication Date
Tue Jan 16 2018
Journal Name
International Journal Of Science And Research (ijsr)
The Effect of Woods' Strategy on Achieving of Second Grade Students in Physics
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: The aim of this research is to investigate the impact of Woods ' strategy in collecting second graders average for physics. To achieve the objective researcher coined the following hypothesis: there was no statistically significant difference at a level (0.05) between the average grades of the experimental group students studying physics as Woods and strategy between the average control group students who are studying the same article in the regular way. Test collection. Search sample amounted to (83) students and (42) students for the experimental group, and (41) students for the control group. Students were subjected to test experiment is composed of (30) after the completion of the experiment. And use appropriate statistical methods re

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Publication Date
Sun Feb 03 2019
Journal Name
Iraqi Journal Of Physics
Effect of CuI concentration on structural and optical properties of PVA: CuI nanocomposites
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The nanocomposite on the base of synthesis Copper iodide
nanoparticles and polyvinyl alcohol (PVA/CuI) with different
concentration of CuI were obtained using casting technique.
PVA/CuI polymer composite samples have been prepared and
subjected to characterizations using FTIR spectroscopy, The FTIR
spectral analysis shows remarkable variation of the absorption peak
positions with increasing CuI concentration. The obtained results by
X-ray diffraction indicated the formation of cubic CuI particles. The
effects of CuI concentrations on the optical properties of the PVA
films were studied in the region of wavelength, (190-1100) nm.
From the derivation of Tauc's relation it was found that the direct
allowed t

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Publication Date
Thu Feb 19 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of zirconia surface treatments on the shear bond strength of veneering ceramic
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Background: The aim of the study was to investigate the effect of surface treatments of zirconia (grinding and sandblast with 50μm, 100 μm) on shear bond strength between zirconia core and veneering ceramic. Material and methods: Twenty-eight presintered Y-TZP ceramic specimens (IPS e.max ZirCAD, Ivoclar vivadent) were fabricated and sintered according to manufacturer’s instructions. The core specimens were divided randomly in to 4 groups, group 1: no surface treatment, group2: zirconia specimens were ground with silicon carbide paper up to1200 grit under water cooling, group3: zirconia specimens were ground and sandblast with 100 μm alumina, group 4: zirconia specimens were ground and sandblast with 50 μm alumina. Surfa

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Study the effect of acid immersion on the hardness of (Epoxy – Granite) composite
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This work has been done with using of epoxy resin mixed with Granite powder were weighted by percent volume (5,10,15, and 20)%and then mixed with epoxy polymer to compose polymer composite. Hand lay-up technique is used in fabrication of the composite samples. Hardness test was carried out for the proper samples in both normal condition and after immersion in HCL (1 M and 2 M) solutions for periods ranging up to 10 weeks. After comparing the results between the polymer and their composite, the hardness increased with increasing Granite weight percent, it was found that Hardness were greater for the composites before immersion compared with their values after immersion.

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