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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 empirical and predicted data were adopted in a mathematical model for oxygen mass transfer to predict the oxygen profile along the reactor. The predicted results have been validated with the experimental results. The simulated results based on the dispersion model for the riser and down comer and the perfect mixed model for the gas-liquid separator, agreed well with the experimental results over the studied range of operating conditions.

 

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Publication Date
Mon Jun 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Simulation of material requirements planning system According to FOQ, EOQ, L4L A study in the General Company for woolen industries / blankets factory
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This paper is submitted as anew approach to simulate manufacturing control & planning system to define the problem of designing control system on the needs for materials.

Production planning & control is a total and complex operation, resides in the essence of manufacturing companies operations. The successful process of production planning and control systems is critical for the staying of manufacturing organizations in markets leading to the increasing consumer competition and which dominate most of manufacturing sectors because of the market oriented economy , thus , what has happened previously , that the companies possessed a great inventory of crude material, components, and groupings and they use in flexible techni

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Crossref
Publication Date
Sun Feb 01 2015
Journal Name
Journal Of Engineering
Impact Analysis of Reinforced Concrete Columns with Side Openings Subjected to Eccentric Axial Loads
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In this research the behavior of reinforced concrete columns with large side openings under impact loads was studied. The overall cross sectional dimensions of the column specimens used in this research were (500*1400) mm with total height of (14000) mm. The dimensions of side openings were (600*2000) mm. The column was reinforced with (20) mm diameter in longitudinal direction, while (12) mm ties were used in the transverse direction. The effect of eccentric impact loads on the horizontal and vertical displacement for this column was studied.                              &

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Publication Date
Mon Feb 02 2015
Journal Name
Journal Of Engineering, University Of Baghdad
'Impact Analysis of Reinforced Concrete Columns with Side Openings Subjected to Eccentric Axial Loads
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Publication Date
Tue Jun 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Between Partial Least Square Regression(PLSR) and Tree Regression by Using Simulation(RT).
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This research discussed, the process of comparison between the regression model of partial least squares and tree regression, where these models included two types of statistical methods represented by the first type "parameter statistics" of the partial least squares, which is adopted when the number of variables is greater than the number of observations and also when the number of observations larger than the number of variables, the second type is the "nonparametric statistic" represented by tree regression, which is the division of data in a hierarchical way. The regression models for the two models were estimated, and then the comparison between them, where the comparison between these methods was according to a Mean Square

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Crossref
Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Robust Estimation OF The Partial Regression Model Using Wavelet Thresholding
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            Semi-parametric regression models have been studied in a variety of applications and scientific fields due to their high flexibility in dealing with data that has problems, as they are characterized by the ease of interpretation of the parameter part while retaining the flexibility of the non-parametric part. The response variable or explanatory variables can have outliers, and the OLS approach have the sensitivity to outliers. To address this issue, robust (resistance) methods were used, which are less sensitive in the presence of outlier values in the data. This study aims to estimate the partial regression model using the robust estimation method with the wavel

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Crossref
Publication Date
Mon Jun 01 2015
Journal Name
Iraqi Journal Of Science
Simulation of Solar Coronal Magnetic Field Using Potential Field Model
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In this paper, 3D simulation of the global coronal magnetic field, which use observed line of sight component of the photosphere magnetic field from (MDI/SOHO) was carried out using potential field model. The obtained results, improved the theoretical models of the coronal magnetic field, which represent a suitable lower boundary conditions (Bx, By, Bz) at the base of the linear force-free and nonlinear force free models, provides a less computationally expensive method than other models. Generally, very high speed computer and special configuration is needed to solve such problem as well as the problem of viewing the streamline of the magnetic field. For high accuracy special mathematical treatment was adopted to solve the computation comp

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Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
Investigating of Charge Transfer in Cu/F8 Using Donor-Acceptor Model due Quantum Transition
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in this paper, we study and investigate a simple donor-acceptor model for charge transfer formation using a quantum transition theory. The transfer parameters which enhanced the charge transfer and the rate of the charge transfer have been calculated. Then, we study the net charge transfer through interface of Cu/F8 contact devices and evaluate all transfer coefficients. The charge transfer rate of transfer processes is found to be dominated in the low orientation free energy and increased a little in decreased potential at interface comparison to the high potential at interface. The increased transition energy results in increasing the orientation of Cu to F8. The transfer in the system was more active when the system has large driving for

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Crossref (4)
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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Estimation of parameters of two-dimensional sinusoidal signal model by employing Deferential Evaluation algorithm and the use of Sequential approach in estimation
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Estimation the unknown parameters of a two-dimensional sinusoidal signal model is an important and a difficult problem , The importance of this model  in modeling Symmetric gray- scale texture image . In this paper, we propose employment Deferential Evaluation algorithm and the use of Sequential approach to estimate the unknown frequencies and amplitudes of the 2-D sinusoidal components when the signal is affected by noise. Numerical simulation are performed for different sample size, and various level of standard deviation to observe the performance of this method in estimate the parameters of 2-D sinusoidal signal model , This model was used for modeling  the Symmetric gray scale texture image and estimating by using

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Crossref
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Bioremediation of Soil Contaminated with 2,4-D Herbicide Using Bioslurry Reactor
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Ex-situ bioremediation of 2,4-D herbicide-contaminated soil was studied using a slurry bioreactor operate at aerobic conditions. The performance of the slurry bioreactor was tested for three types of soil (sand, sandy loam and clay) contaminated with different concentration of 2,4-D, 200,300and500mg/kg soil. Sewage sludge was used as an inexpensive source of microorganisms which is available in large quantities in wastewater treatment plants. The results show that all biodegradation experiments demonstrated a significant decreases in 2,4-D concentration in the tested soils. The degradation efficiency in the slurry bioreactor decreases as the initial concentration of 2,4-D in the soils increases.A 100 % removal was achieved at initial con

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Crossref
Publication Date
Tue Dec 01 2009
Journal Name
Iraqi Journal Of Physics
Simulation of an ion Optical Transport and Focusing System
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A simulated ion/electron optical transport and focusing system has been put forward to
be mounted on high voltage transmission electron microscope for in situ investigations.
The suggested system consists of three axially symmetric electrostatic lenses namely an
einzel lens, an accelerating immersion lens, and a decelerating immersion lens, in addition
to an electrostatic quadrupole doublet lens placed on the image side. The electrodes
profile of these lenses is determined from the proposed axial field distributions. The
optical properties of the whole system have been computed together with the trajectory of
the accelerated charged-particles beam along the optical axis of the system. The computed
dimensions of th

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