Preferred Language
Articles
/
alkej-869
PDF Comparison based on Various FSO Channel Models under Different Atmospheric Turbulence
...Show More Authors

Recently, wireless communication environments with high speeds and low complexity have become increasingly essential. Free-space optics (FSO) has emerged as a promising solution for providing direct connections between devices in such high-spectrum wireless setups. However, FSO communications are susceptible to weather-induced signal fluctuations, leading to fading and signal weakness at the receiver. To mitigate the effects of these challenges, several mathematical models have been proposed to describe the transition from weak to strong atmospheric turbulence, including Rayleigh, lognormal, Málaga, Nakagami-m, K-distribution, Weibull, Negative-Exponential, Inverse-Gaussian, G-G, and Fisher-Snedecor F distributions. This paper extensively studies and analyses different probability density functions (PDFs) that govern the FSO channel, considering various channel models. This paper aims to comprehensively understand how FSO channels can be effectively modeled using different PDFs. Accurate modeling is crucial for designing FSO systems that can operate optimally under potential environmental conditions. Selecting the appropriate PDF model plays a crucial role in determining the FSO channel's performance during system design. With a multitude of PDF models available, this study aims to identify the most effective PDF model to be employed in FSO channel modeling.

 

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Dec 26 2017
Journal Name
Al-khwarizmi Engineering Journal
Experimental Modeling and Optimization of Fatigue Life and Hardness of Carbon Steel CK35 under Dynamic Buckling
...Show More Authors

Abstract

 

The aim of this paper is to model and optimize the fatigue life and hardness of medium carbon steel CK35 subjected to dynamic buckling. Different ranges of shot peening time (STP) and critical points of slenderness ratio which is between the long and intermediate columns, as input factors, were used to obtain their influences on the fatigue life and hardness, as main responses. Experimental measurements of shot peening time and buckling were taken and analyzed using (DESIGN EXPERT 8) experimental design software which was used for modeling and optimization purposes. Mathematical models of responses were obtained and analyzed by ANOVA variance to verify the adequacy of the models. The resul

... Show More
View Publication Preview PDF
Publication Date
Tue Oct 20 2020
Journal Name
International Journal Of Civil Engineering
Structural Performance Under Monotonic Static Loading of Reinforced Concrete Gable Roof Beams with Multiple Web Openings
...Show More Authors

In the present study, an attempt has been made to experimentally investigate the flexural performance of ten simply supported reinforced concrete gable roof beams, including solid control specimen (i.e., without openings) and nine beams with web openings of different dimensions and configurations. The nine beams with openings have identical reinforcement details. All beams were monotonically loaded to failure under mid-span loading. The main variables were the number of the created openings, the total area of the created openings, and the inclination angle of the posts between openings. Of interest is the load-carrying capacity, cracking resistance and propagation, deformability, failure mode, and strain development that represent the behav

... Show More
View Publication Preview PDF
Scopus (1)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sun Apr 30 2023
Journal Name
Sabrao Journal Of Breeding And Genetics
STUDY OF THE GENETIC DIVERSITY OF SOME GENOTYPES OF MAIZE UNDER TWO LEVELS OF NITROGEN FERTILIZATION
...Show More Authors

The present study aimed to determine the genetic divergence of seven maize genotypes (Al-Maha, Sumer, Al-Fajr, Baghdad, 5018, 4 × 1 single hybrid, and 4 × 2 single hybrid) under two varied levels of nitrogen fertilization (92 and 276 kg N ha-1). The experiment occurred in 2022 in a randomized complete block design (RCBD) with a split-plot arrangement and three replications at the College of Agricultural Engineering Sciences, University of Baghdad, Iraq. The nitrogen fertilization levels served as main plots, with the maize genotypes allocated as the subplots. The results revealed that genetic variance was higher than the environmental variance for most traits, and the coefficient of phenotypic variation was close to the genetic va

... Show More
View Publication
Scopus (7)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Thu Apr 05 2018
Journal Name
Acs Applied Nano Materials
Direct Formation of 2D-MnO<sub><i>x</i></sub> under Conditions of Water Oxidation Catalysis
...Show More Authors

We describe the synthesis and characterization of a novel 2D-MnOx material using a combination of HR-TEM, XAS, XRD, and reactivity measurements. The ease with which the 2D material can be made and the conditions under which it can be made implies that water oxidation catalysts previously described as “birnessite-like” (3D) may be better thought of as 2D materials with very limited layer stacking. The distinction between the materials as being “birnessite-like” and “2D” is important because it impacts on our understanding of the function of these materials in the environment and as catalysts. The 2D-MnOx material is noted to be a substantially stronger chemical oxidant than previously noted for other birnessite-like manganese oxi

... Show More
View Publication
Scopus (10)
Crossref (10)
Scopus Clarivate Crossref
Publication Date
Sun Dec 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Free Vibration Analysis of Laminated Composite Plates with General Boundary Elastic Supports Under Initial Thermal Load
...Show More Authors

Free vibration behavior was developed under the ratio of critical buckling temperature of laminated composite thin plates with the general elastic boundary condition. The equations of motion were found based on classical laminated plate theory (CLPT) while the solution functions consists of trigonometric function and a continuous function that is added to guarantee the sufficient smoother of the so-named remaining displacement function at the boundaries, in this research, a modified Fourier series were used, a generalized procedure solution was developed using Ritz method combined with the imaginary spring technique. The influences of many design parameters such as angles of layers, aspect ratio, thickness ratio, and ratio of initial in-

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 30 2013
Journal Name
Al-kindy College Medical Journal
Occurrence of Amoebic Versus Bacillary Dysentery among Children Under Five Years of Age in Baghdad City
...Show More Authors

Background: During Annual statistical report published by the Iraqi ministry of health the year 2004 showed that mortality rate was 0.15 per 1000 of diarrheal episodes among children under five years.Objectives: To study the occurrence of Shigellosis and Entamoeba histolytica in a sample of children from certain hospitals in Baghdad and determine its relation to some demographic factors.Methods: This cross sectional study was carried out in Baghdad city involving 400 children with bloody diarrhea under five years of age attending four hospitals, 130 cases from Central Pediatric Hospital, 110 cases from Al Mansoor Pediatric Hospital, 90 cases from Al Kadhimya Teaching Hospital and 70 cases from Mohammed Baaqir Al Hakeem Hospital for the p

... Show More
View Publication Preview PDF
Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Feasibility Study of a Solar Flat Plate Collector for Domestic and Commercial Applications under Iraq Climate
...Show More Authors

View Publication
Scopus (10)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Sat Jun 30 2007
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Corrosion Inhibition of Carbon Steel under Two Phase Flow (Water-Petroleum) Simulated by Turbulently Agitated System
...Show More Authors

The corrosion of carbon steel in single phase (water with 0.1N NaCl ) and two immiscible phases (kerosene-water) using turbulently agitated system is investigated. The experiments are carried out for Reynolds number (Re) range of 38000 to 95000 corresponding  to rotational velocities from 600 to 1400 rpm using circular disk turbine agitator at 40 0C. In two-phase system test runs are carried out in aqueous phase (water) concentrations of 1 % vol., 5 % vol., 8% vol., and 16% vol. mixed with kerosene at various Re. The effect of Reynolds number (Re), percent of dispersed phase, dispersed drops diameter, and number of drops per unit volume on the corrosion rate is investigated and discussed. Test runs are carried out using two types of

... Show More
View Publication Preview PDF
Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
OPTIMAL DESIGN OF MODERATE THICK LAMINATED COMPOSITE PLATES UNDER STATIC CONSTRAINTS USING REAL CODING GENETIC ALGORITHM
...Show More Authors

The objective of the current research is to find an optimum design of hybrid laminated moderate thick composite plates with static constraint. The stacking sequence and ply angle is required for optimization to achieve minimum deflection for hybrid laminated composite plates consist of glass and carbon long fibers reinforcements that impeded in epoxy matrix with known plates dimension and loading. The analysis of plate is by adopting the first-order shear deformation theory and using Navier's solution with Genetic Algorithm to approach the current objective. A program written with MATLAB to find best stacking sequence and ply angles that give minimum deflection, and the results comparing with ANSYS.

View Publication Preview PDF
Crossref
Publication Date
Mon Jan 01 2024
Journal Name
2nd International Conference For Engineering Sciences And Information Technology (esit 2022): Esit2022 Conference Proceedings
Numerical solution to inverse coefficient problem for hyperbolic equation under overspecified condition of general integral type
...Show More Authors

View Publication
Scopus Crossref