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Checking the Accuracy of Selected Formulae for both Clear Water and Live Bed Bridge Scour
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Due to severe scouring, many bridges failed worldwide. Therefore, the safety of the existing bridge (after contrition) mainly depends on the continuous monitoring of local scour at the substructure. However, the bridge's safety before construction mainly depends on the consideration of local scour estimation at the bridge substructure. Estimating the local scour at the bridge piers is usually done using the available formulae. Almost all the formulae used in estimating local scour at the bridge piers were derived from laboratory data. It is essential to test the performance of proposed local scour formulae using field data. In this study, the performance of selected bridge scours estimation formulae was validated and statistically tested using field data for existing bridges in Canada, Iraq (Kufa, Najaf), Pakistan, Bangladesh, and India. The validated formulae were HEC-18, Forehlich, and Johnson. The validation was conducted by comparing the predicted local scour depths obtained from applying the above selected formulae with the local scour depths obtained from the field data. The comparison between them was presented using a scattergram. However,  statistical tests were used to present the accuracy of the local scour predictions. The tests were conducted using three statistical indices, namely, Theil’s coefficient (U), Mean Absolute Error (MAE), and Root Mean Square Error (RMSE). Among the tested formulae, the Jonson formula gave satisfactory performance since the values of U, MAE, and RMSE were found to be 0.112, 1.351, and 1.650, respectively.

 

 

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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Augmentation of Nanofluids Heat transfer in a Circular Tube with Baffled Winged Twisted Swirl Generator
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This article introduces a numerical study on heat exchange and corrosion coefficients of Zinc–water nanofluid stream in a circular tube fitted with swirl generator utilizing CFD emulation. Different  forms of swirl generator which have the following properties of plain twisted tape (PTT) and baffle wings twisted tape (BTT) embeds with various ratio of twisting (y = 2.93, 3.91 and 4.89), baffle inclination angles (β = 0°, - 30° and 30) joined with 1%, 1.5% and 2% volume fraction of ZnO nanofluid were utilized for simulation. The results demonstrated that the heat and friction coefficients conducted by these two forms of vortex generator raised with Reynolds number, twist ratio and baffle inclination angles decreases. Likewise, t

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Publication Date
Thu Dec 13 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Effectiveness of an Education Program ConcerningCardiotocography on Nurses- MidwivesPractice in Maternity Hospitals at Baghdad City.
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Objectives: To identify the effectiveness program on nurse- midwife practice concerning performed
cardiotocography to pregnant women and to find out the relationship between nurse- midwife practice and
certain studied variables.
Methodology: A quasi-experimental design (pretest-post test approach) was conducted at three sector AlRussafa
directorate, AL- Karckh directorate and Medical City Directorate from the period of March, 26th 2014
to August, 30th 2015. A non-probability sample consisted of (130) nurse -midwives were selected and divided
into two groups (65) nurses-midwives (case group) who exposed to the educational program and (65 ) nursesmidwives
who didn't expose to the program considered as control group . D

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Publication Date
Sun Mar 01 2009
Journal Name
Laser And Particle Beams
Surface morphology modifications of human teeth induced by a picosecond Nd:YAG laser operating at 532nm
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Scopus (11)
Scopus
Publication Date
Tue Jun 01 2021
Journal Name
International Medical Journal Vol. 28, Supplement No. 1, Pp. 46 - 48 , June 2021
Association of enamel defects with nutritional status among primary schools students in Al-Najaf city
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Scopus (2)
Scopus
Publication Date
Sat Dec 31 2011
Journal Name
Al-khwarizmi Engineering Journal
Simulation of Oxygen Mass Transfer in an Internal Loop Airlift Reactor with Axial Dispersion Model
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The effect of superficial gas velocity within the range 0.01-0.164 m/s on gas holdup (overall, riser and down comer), volumetric oxygen mass transfer coefficient, liquid circulation velocity was studied in an internal loop concentric tubes airlift reactor (working volume 45 liters). It was shown that as the usg increases the gas holdup and also the liquid circulation velocity increase. Also it was found that increasing superficial gas velocity lead to increase the interfacial area that increases the overall oxygen mass transfer coefficient. The hydrodynamic experimental results were modeled with the available equations in the literature. The predicted data gave an acceptable accuracy with the empirical data.

The final

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Publication Date
Sun Nov 05 2017
Journal Name
International Journal Of Science And Research
Production of Biodiesel from Waste Cooking Oil using Cao-Egg Shell Waste Derived Heterogeneous Catalyst
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Biodiesel is an environmentally friendly fuel and a good substitution for the fossil fuel. However, the purity of this fuel is a major concern that challenges researchers. In this study, a calcium oxide based catalyst has been prepared from local waste eggshells by the calcination method and tested in production biodiesel. The eggshells were powdered and calcined at different temperatures (700, 750, 800, 850 and 900 °C) and periods of time (1, 2, 3, 4 and 5 hr.). The effect of calcination temperature and calcination time on the structure and activity of the solid catalyst were examined by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Brunaure-Emmett-Teller (BET). The optimum catalyst performance was obtained at 900 °C

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Publication Date
Thu Apr 01 2021
Journal Name
International Journal Of Drug Delivery Technology
Phytochemical investigation of some chemical compounds present in vicia villosa l. Widely grown in Iraq
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Scopus
Publication Date
Thu Jan 23 2020
Journal Name
Acoustics Australia
Absorption Coefficient of a Double-Layer Inhomogeneous Micro-perforated Panel Backed with Multiple Cavity Depths
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Double-layer micro-perforated panels (MPPs) have been studied extensively as sound absorption systems to increase the absorption performance of single-layer MPPs. However, existing proposed models indicate that there is still room for improvement regarding the frequency bands of absorption for the double-layer MPP. This study presents a double-layer MPP formed with two single MPPs with inhomogeneous perforation backed by multiple cavities of varying depths. The theoretical formulation is developed using the electrical equivalent circuit method to calculate the absorption coefficient under a normal incident sound. The simulation results show that the proposed model can produce absorption coefficient with wider absorption bandwidth compared w

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Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
Annealing Effect on Some Optical Properties of Cr2O3 Thin Films Prepared by Spray Pyrolysis Technique
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Cr2O3 thin films have been prepared by spray pyrolysis on a glass substrate. Absorbance and transmittance spectra were recorded in the wavelength range (300-900) nm before and after annealing. The effects of annealing temperature on absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of dielectric constant and optical conductivity were expected. It was found that all these parameters increase as the annealing temperature increased to 550°C.

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Crossref
Publication Date
Sat May 02 2020
Journal Name
Plant Archives
MEASUREMENT OF ASBESTOS FIBERS CONCENTRATIONS IN SOME DENSE AREAS IN BAGHDAD, IRAQ, IN WINTER 2020
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Asbestos is a hazard pollutant to human health, exposure to asbestos cause serious health effects and wide range of asbestos-related diseases such as asbestosis, lung cancer and malignant mesothelioma and it has been classified as carcinogen by the World Health Organization WHO which cause a carcinogenic effects. Fibers of asbestos are mainly released from friction product in brakes and clutch linings and from reinforce agent in the asbestos cement industry. The aim of this was to evaluate the levels of asbestos fibers in surroundings air of some dense traffic points in Baghdad, through winter 2020. Materials and Methods: Samples of airs was carried out by directing air flow to a mixed cellulose ester membrane filter mounted on an open face

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