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Virtual failure influence of Roseires dam on Khartoum city using HEC-RAS Hydraulic simulation modeling
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Dam break is series phenomenon that can result in fatal consequences and loss of properties. Unfortunately, the observed consequences can only be available after the dam breaks. Therefore, it is important to anticipate what will happen prior to dam break to issue suitable warning and locate the possible risk areas. This study attempts to simulate the case of dam break in Blue Nile at Roseires dam and see its consequences downstream. Roseires dam lies at a distance of 630 km south of Khartoum, Sennar dam lies at about 260 km downstream of Roseires dam. In this study hydraulic model is developed based of Hydraulic Engineering Centre (HEC), River Analysis System (RAS), and HEC- RAS. The HEC-RAS based model is calibrated and validated using observed data of the Blue Nile for several flood years. The calibrated and validated model is used to analyze the impact of flood wave due to dam break failure of Roseires dam to provide the following information: the maximum discharge, the maximum water level, the maximum velocity, the velocity and depth profiles, the flooding extent, etc. Several dam break scenarios that cover the possible failure modes were considered and the scenario that gives the worst situation is present in this paper. Piping is considered as failure mode with different failure parameters. It was found that failure of Roseires dam result in overtopping failure of Sennar dam due to the inability of the Sennar reservoir and dam to withstand the flood wave. The results also indicated that the maximum flood wave resulting from the failure of Roseires dam reaches Khartoum in 4, 6, 7 and 9 days when the maximum flow is 33105, 14724, 13249 and 12443 m3/s respectively the cities (Roseires, Sennar, Wad Medani and Khartoum ). The respective water surface level of flood wave is 481.01, 428.37 and 382.5 m in Roseires, Sennar and Khartoum and the wave speed at Khartoum is 8.97 m/s.

Publication Date
Fri Jan 20 2023
Journal Name
Journal Of Electronic Materials
Influence of Dry and Wet Etching on AlInSb Contact Resistivity, Transfer Length, and Sheet Resistance Using Circular Transmission Model
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Publication Date
Wed Sep 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
Using simulation to estimate parameters and reliability function for extreme value distribution
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   This study includes Estimating scale parameter, location parameter  and reliability function  for Extreme Value (EXV) distribution by two methods, namely: -
- Maximum Likelihood Method (MLE).
- Probability Weighted Moments Method (PWM).

 Used simulations to generate the required samples to estimate the parameters and reliability function of different sizes(n=10,25,50,100) , and give real values for the parameters are and , replicate the simulation experiments (RP=1000)

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Publication Date
Wed Apr 25 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On Reliability Estimation for the Exponential Distribution Based on Monte Carlo Simulation
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        This Research deals with estimation the reliability function for two-parameters Exponential distribution, using different estimation methods ; Maximum likelihood, Median-First Order Statistics, Ridge Regression, Modified Thompson-Type Shrinkage and Single Stage Shrinkage methods. Comparisons among the estimators were made using Monte Carlo Simulation based on statistical indicter mean squared error (MSE) conclude that the shrinkage method perform better than the other methods

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Publication Date
Sun Apr 23 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Influence Activation Function in Approximate Periodic Functions Using Neural Networks
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The aim of this paper is to design fast neural networks to approximate periodic functions, that is, design a fully connected networks contains links between all nodes in adjacent layers which can speed up the approximation times, reduce approximation failures, and increase possibility of obtaining the globally optimal approximation. We training suggested network by Levenberg-Marquardt training algorithm then speeding suggested networks by choosing most activation function (transfer function) which having a very fast convergence rate for reasonable size networks.             In all algorithms, the gradient of the performance function (energy function) is used to determine how to

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Publication Date
Mon Aug 14 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Simulation of the Frequency Doubled Nd:YAG Laser Effect on the Retina
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The  present  study  was  conducted  with  a  view  to  determine

whether focal laser therapy results in avisual recovery and regression of macular odema in patients with non-proliferative diabetic maculopathy. A

Frequency doubled Nd:YAG laser was used for the treatment of diabetic maculopathy. For several has been studied and the treatment results were discussed. The study evaluates 14 eyes of 8 diabetic patients. Mathematical model of the laser interaction with the retinal tissue is demonstrated and analysis results are explained and compared with the recent experimental and mathematical models . It has been shown that the laser treatment of the retinal diabetic macolapathy ,

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Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Modeling of the Effect of MgO and ZrO2 on Sintering of Alumina
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  This research  studyies the effect of MgO and ZrO2 as additives in sintering Al2O3 . The experimental results are modeled using ( L2 _ regression) technique , sintered density and grain size rate measurments were  accounted by utilizing experimental results of undoped , MgO doped and ZrO2  doped alumina impregrated with spherical large pores in final stage of sintering . The effect of each additive is inhibitian of the grain growth and increasing the densification rate which enhances the kinietics of densification and the removal of large and small pores.

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Publication Date
Fri Aug 28 2020
Journal Name
Iraqi Journal Of Science
A study of the Effect of Urbanization on Annual Evaporation Rates in Baghdad City Using Remote Sensing
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The city of Baghdad has recently witnessed an increase in urban land due to the recent economic growth, which negatively affected the environment of the study area through the retraction of the agricultural lands surrounding the city. Therefore, we studied the relationship between increasing urban expansion and changes in the local climate of Baghdad for the period from 2008 to 2018. The information derived from the satellites utilized in this search showed the changes in ground cover during the study period, while the evaporation rate data source from the European Center for Forecasting (ECMWF) confirmed the effects of urban expansion on evaporation rates. Increasing urbanization increased evaporation rates and decreased vegetation degr

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Publication Date
Sat Jun 02 2018
Journal Name
Agroforestry Systems
Biomass and buffer management practice effects on soil hydraulic properties compared to grain crops for claypan landscapes
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Publication Date
Sun Jan 30 2022
Journal Name
Iraqi Journal Of Science
Detection of Albumin and Urea in Kidney Failure Patients by Optical Biosensor
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The major function of the kidney is the filtration and secretion of the final products of metabolism and the excess of electrolytes. The term kidney failure denotes inability of the kidneys to perform excretory function leading to retention of nitrogenous waste products from the blood. Biosensor are most accurate, with a rapid diagnosis ,more costly method than the traditional method to avoid any biological changes in blood sample that lead to changes optical characteristic (refractive index and absorption) of blood sample. The current study was designed to single mode  more Sensitivity than multi mode for Biomarkers  were recorded for Albumin 5447.06, 5193.93 and Urea sample 2623.14, 1998.44  in sm and mm respectively .

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Publication Date
Thu Dec 01 2022
Journal Name
Al-khwarizmi Engineering Journal
The Influence of Support Materials on The Photo-Fenton-like Degradation of Azo Dye Using Continuous Nanoparticles Fixed-bed Column
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This study used a continuous photo-Fenton-like method to remediate textile effluent containing azo dyes especially direct blue 15 dye (DB15). A Eucalyptus leaf extract was used to create iron/copper nanoparticles supported on bentonite for use as catalysts (E@B-Fe/Cu-NPs). Two fixed-bed configurations were studied and compared. The first one involved mixing granular bentonite with E@B-Fe/Cu-NPs (GB- E@B-Fe/Cu-NPs), and the other examined the mixing of E@B-Fe/Cu-NPs with glass beads (glass beads-E@B-Fe/Cu-NPs) and filled to the fixed-bed column. Scanning electron microscopy (SEM), zeta potential, and atomic forces spectroscopy (AFM) techniques were used to characterize the obtained particles (NPs). The effect of flow rate and DB15 concent

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