Analysis of the Capacity, Spectral Efficiency and Probability of Outage of Adaptive Mobile Channel for WiMAX System
Publication Date
Tue Dec 31 2013
Journal Name
Al-khwarizmi Engineering Journal
Numerical Analysis of Double Diffusive Laminar Natural Convection in a Right Angle Triangular Solar Collector
double diffusion
heat and mass transfer
laminar natural convection
solar collector
A numerical study of the double-diffusive laminar natural convection in a right triangular solar collector has been investigated in present work. The base (absorber) and glass cover of the collector are isothermal and isoconcentration surfaces, while the vertical wall is considered adiabatic and impermeable. Both aiding and opposing buoyancy forces have been studied. Governing equations in vorticity-stream function form are discretized via finite-difference method and are solved numerically by iterative successive under relaxation (SUR) technique. Computer code for MATLAB software has been developed and written to solve mathematical model. Results in the form of streamlines, isotherms, isoconcentration, average Nusselt, and average Sherw
... Show MorePublication Date
Tue Jan 01 2008
Journal Name
Tikrit Journal Of Engineering Sciences
Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Time Series Analysis of Total Suspended Solids Concentrations in Euphrates River in Al-Nasria Province
The monthly time series of the Total Suspended Solids (TSS) concentrations in Euphrates River at Nasria was analyzed as a time series. The data used for the analysis was the monthly series during (1977-2000).
The series was tested for nonhomogenity and found to be nonhomogeneous. A significant positive jump was observed after 1988. This nonhomogenity was removed using a method suggested by Yevichevich (7). The homogeneous series was then normalized using Box and Cox (2) transformation. The periodic component of the series was fitted using harmonic analyses, and removed from the series to obtain the dependent stochastic component. This component was then modeled using first order autoregressive model (Markovian chain). The above a
... Show MorePublication Date
Tue Dec 31 2024
Journal Name
International Review On Modelling And Simulations (iremos)
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Finite Element Analysis of Reinforced Concrete T-Beams with Multiple Web Openings under Impact Loading
Beams
web openings
impact loading.
In this study, a three-dimensional finite element analysis using ANSYS 12.1 program had been employed to simulate simply supported reinforced concrete (RC) T-beams with multiple web circular openings subjected to an impact loading. Three design parameters were considered, including size, location and number of the web openings. Twelve models of simply supported RC T-beams were subjected to one point of transient (impact) loading at mid span. Beams were simulated and analysis results were obtained in terms of mid span deflection-time histories and compared with the results of the solid reference one. The maximum mid span deflection is an important index for evaluating damage levels of the RC beams subjected to impact loading. Three experi
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Publication Date
Fri Sep 02 2022
Journal Name
Frontiers In Built Environment
Thermal analysis of horizontal earth-air heat exchangers in a subtropical climate: An experimental study
The earth-air heat exchanger (EHX) has a promising potential to passively save the energy consumption of traditional air conditioning systems while maintaining a high degree of indoor comfort. The use of EHX systems for air conditioning in commercial and industrial settings offers several environmental benefits and is capable of operating in both standalone and hybrid modes. This study tests the performance and effectiveness of an EHX design in a sandy soil area in Baghdad, Iraq. The area has a climate of the subtropical semi-humid type. Ambient air temperatures and soil temperatures were recorded throughout the months of 2021. During the months of January and June, the temperatures of the inlet and outflow air at varying air veloci
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Publication Date
Mon Mar 01 2021
Journal Name
Iraqi Journal Of Physics
Studying the Correlation Between Supermassive Black Holes and Star Formation Rate for Samples of Seyfert Galaxies (Type 1 and 2)
Galaxies – Techniques
spectroscopy
Active galaxies
Seyfert.
An optical spectroscopic study is reported in this article to study the correlation between the supermassive black hole (SMBH) and the star formation rate (SFR) for a sample of Seyfert galaxies type (I and II). The study focused on 45 galaxy of Seyfert 1, in addition to 45 galaxy of Seyfert 2, where these samples have been selected form different survey of Salon Digital Sky Survey (SDSS). The redshift (z) of these objects were between (0.02 – 0.26). The results of Seyfert 1 galaxies shows that there good correlation between the SMBH and the SFR depending on statistical analysis parameter named Spearman’s Rank Correlation in a factor of (ρ=0.609), as well as the Seyfert 2 galaxies results show a good correlation between the SMBH
... Show More
Publication Date
Sun Mar 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Evolution and set up the maps for solar radiation of Iraq using Data observation and Angstrom model during monthly July2017
Abstract<p>The development that solar energy will have in the next years needs a reliable estimation of available solar energy resources. Several empirical models have been developed to calculate global solar radiation using various parameters such as extraterrestrial radiation, sunshine hours, albedo, maximum temperature, mean temperature, soil temperature, relative humidity, cloudiness, evaporation, total perceptible water, number of rainy days, and altitude and latitude. In present work i) First part has been calculated solar radiation from the daily values of the hours of sun duration using Angstrom model over the Iraq for at July 2017. The second part has been mapping the distribution of so</p>
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(1)
Publication Date
Mon Mar 01 2021
Journal Name
Iraqi Journal Of Physics
Studying the Correlation Between Supermassive Black Holes and Star Formation Rate for Samples of Seyfert Galaxies (Type 1 and 2)
Galaxies – Techniques: spectroscopy
Active galaxies: Seyfert.
An optical spectroscopic study is reported in this article to study the correlation between the supermassive black hole (SMBH) and the star formation rate (SFR) for a sample of Seyfert galaxies type (I and II). The study focused on 45 galaxy of Seyfert 1, in addition to 45 galaxy of Seyfert 2, where these samples have been selected form different survey of Salon Digital Sky Survey (SDSS). The redshift (z) of these objects were between (0.02 – 0.26). The results of Seyfert 1 galaxies shows that there good correlation between the SMBH and the SFR depending on statistical analysis parameter named Spearman’s Rank Correlation in a factor of (ρ=0.609), as well as the Seyfert 2 galaxies results show a good correlation between the SMBH and
... Show More
Publication Date
Fri Jul 29 2022
Journal Name
Journal For Vascular Ultrasound
A Comparative Study of the Right and Left Carotid Arteries in Relation to Age for Patients With Diabetes and Hypertension
Introduction:
Introduction: Age
hypertension
and diabetes can cause significant alterations in arterial structure and function
including
changes in lumen diameter (LD)
intimal-medial thickness (IMT)
flow velocities
and arterial compliance. These are also considered
risk markers of atherosclerosis and cerebrovascular disease. A difference between right and left carotid artery blood flow and
IMT has been reported by some researchers
and a difference in the incidence of nonlacunar stroke has been reported between
the right and left brain hemispheres. The aim of this study was to determine whether there are differences between the right and
left common carotid arteries and internal carotid arteries in patients with hypertension and diabetes for 2 age groups.
Methods: We studied 250 patients with both diabetes and hypertension. Patients were divided into 2 age groups with the
old age group being 56 to 75 years and the young age group 35 to 55 years. The bilateral common carotid and internal carotid
arteries were evaluated with B-mode ultrasound and Doppler examinations. The LD and IMT were measured for both common
carotid arteries
and spectral waveform parameters and indices were recorded for both internal carotid arteries.
Results: The difference in LD between the left and right common carotid arteries for the old age group was 11.64% and for the
young age group was 6.42%
with significant P values of <.05 for both age groups. The difference in IMT between the left and
right common carotid arteries was 18.27% in the old age group compared with 15.38% in the young age group
with significant
P values of <.05. There was a difference in peak systolic velocity between the left and right internal carotid arteries of 4.85%
in the old age group which was not significant
compared with 14.28% in the young age group with a significant P value <.05
whereas the difference in end-diastolic velocity between the left and right internal carotid arteries was not significant for both
age groups. Differences between the right and left internal carotid arteries for resistive index
pulsatility index
and pressure
gradient were significant only in the young age group.
Conclusion: We found significant differences between the right and left common carotid and internal carotid arteries in
patients with diabetes and hypertension which were more prominent in the young age group. Values for common carotid IMT
and LD were significantly higher in the left common carotid artery versus the right common carotid artery in both age groups.
Differences between the 2 carotid sides may be attributed to anatomic variations in the common carotid artery origins which
lead to differences in stress between the 2 sides
Age, hypertension, and diabetes can cause significant alterations in arterial structure and function, including changes in lumen diameter (LD), intimal-medial thickness (IMT), flow velocities, and arterial compliance. These are also considered risk markers of atherosclerosis and cerebrovascular disease. A difference between right and left carotid artery blood flow and IMT has been reported by some researchers, and a difference in the incidence of nonlacunar stroke has been reported between the right and left brain hemispheres. The aim of this study was to determine whether there are differences between the right and left common carotid arteries and internal carotid arteries in patient
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