Preferred Language
Articles
/
yhdPUpEBVTCNdQwCZJQl
Performance Analysis of FSO under Turbulent Channel Using OSTBC
...Show More Authors

Free Space Optics (FSO) plays a vital role in modern wireless communications due to its advantages over fiber optics and RF techniques where a transmission of huge bandwidth and access to remote places become possible. The specific aim of this research is to analyze the Bit-Error Rate (BER) for FSO communication system when the signal is sent the over medium of turbulence channel, where the fading channel is described by the Gamma-Gamma model. The signal quality is improved by using Optical Space-Time Block- Code (OSTBC) and then the BER will be reduced. Optical 2×2 Alamouti scheme required 14 dB bit energy to noise ratio (Eb/N0) at 10-5 bit error rate (BER) which gives 3.5 dB gain as compared to no diversity scheme. The results show that using Multiple-Input-Multiple-Output (MIMO) technique represented by Alamouti scheme gives the improved BER performance as compared with no diversity (Single-Input-Single-Output (SISO)) technique.

Crossref
View Publication
Publication Date
Fri Feb 02 2024
Journal Name
Iraqi Journal Of Science
Using Sensitivity Analysis in Linear Programming with Practical Physical Applications
...Show More Authors

Linear programming currently occupies a prominent position in various fields and has wide applications, as its importance lies in being a means of studying the behavior of a large number of systems as well. It is also the simplest and easiest type of models that can be created to address industrial, commercial, military and other dilemmas. Through which to obtain the optimal quantitative value. In this research, we dealt with the post optimality solution, or what is known as sensitivity analysis, using the principle of shadow prices. The scientific solution to any problem is not a complete solution once the optimal solution is reached. Any change in the values of the model constants or what is known as the inputs of the model that will chan

... Show More
Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Geotechnical Engineering And Sustainable Construction
Numerical Modeling of Under Reamed Piles Behavior Under Dynamic Loading in Sandy Soil
...Show More Authors

Under-reamed piles defined by having one or more bulbs have the potential for sizeable major sides over conventional straight-sided piles, most of the studies on under-reamed piles have been conducted on the experimental side, while theoretical studies, such as the finite element method, have been mainly confined to conventional straight-sided piles. On the other hand, although several laboratory and experimental studies have been conducted to study the behavior of under-reamed piles, few numer­ical studies have been carried out to simulate the piles' performance. In addition, there is no research to compare and evaluate the behavior of these piles under dynamic loading. Therefore, this study aimed to numerically investigate bearing capaci

... Show More
View Publication
Scopus (2)
Crossref (2)
Scopus Crossref
Publication Date
Sat Aug 31 2019
Journal Name
Association Of Arab Universities Journal Of Engineering Sciences
Improvement of Economic Water Productivity of Cucumber by using Soil Water Retention Technology under Subsurface Trickle Irrigation System
...Show More Authors

Subsurface soil water retention (SWRT) is a recent technology for increasing the crop yield, water use efficiency and then the water productivity with less amount of applied water. The goal of this research was to evaluate the existing of SWRT with the influence of surface and subsurface trickle irrigation on economic water productivity of cucumber crop. Field study was carried out at the Hawr Rajab district of Baghdad governorate from October 1st, to December 31st, 2017. Three experimental treatments were used, treatment plot T1 using SWRT with subsurface trickle irrigation, plot T2 using SWRT with surface trickle irrigation, while plot T3 without using SWRT and using surface tickle irrigation system. The obtained results showed that the e

... Show More
View Publication
Crossref (2)
Crossref
Publication Date
Wed May 10 2023
Journal Name
Journal Of Engineering
Vibration Control Analysis of a Smart Flexible Cantilever Beam Using Smart Material
...Show More Authors

This paper features the modeling and design of a pole placement and output Feedback control technique for the Active Vibration Control (AVC) of a smart flexible cantilever beam for a Single Input Single Output (SISO) case. Measurements and actuation actions done by using patches of piezoelectric layer, it is bonded to the master structure as sensor/actuator at a certain position of the cantilever beam.
The smart structure is modeled based on the concept of piezoelectric theory, Bernoulli -Euler beam theory, using Finite Element Method (FEM) and the state space techniques. The number of modes is reduced using the controllability and observability grammians retaining the first three
dominant vibratory modes, and for the reduced syste

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Sat May 01 2021
Journal Name
Iop Conference Series: Earth And Environmental Science
Evaluation Yield of Okra with Associated Traits Using Analysis Correlation and Path
...Show More Authors
Abstract<p>The study was conducted at the fields of the Department of Horticulture and Landscape Gardening, College of Agriculture Engineering Sciences, University of Baghdad. During the spring 2017. All the recommended practices were followed during experimentation. The experimental material consisted four Genotype it is Batraa, Btera, Mosulle, and local selection. The experiment was applied in Randomized Complete Block Design (RCBD). The objectives of Study were to estimate the some genetic parameters and path coefficient for some traits Okra, The results of statistical analysis for these genotypes were highly significant differences for all traits except the traits number of leaves, the numbe</p> ... Show More
View Publication
Scopus (5)
Crossref (3)
Scopus Crossref
Publication Date
Mon Nov 11 2019
Journal Name
Spe
Modeling Rate of Penetration using Artificial Intelligent System and Multiple Regression Analysis
...Show More Authors
Abstract<p>Over the years, the prediction of penetration rate (ROP) has played a key rule for drilling engineers due it is effect on the optimization of various parameters that related to substantial cost saving. Many researchers have continually worked to optimize penetration rate. A major issue with most published studies is that there is no simple model currently available to guarantee the ROP prediction.</p><p>The main objective of this study is to further improve ROP prediction using two predictive methods, multiple regression analysis (MRA) and artificial neural networks (ANNs). A field case in SE Iraq was conducted to predict the ROP from a large number of parame</p> ... Show More
View Publication Preview PDF
Crossref (7)
Crossref
Publication Date
Fri Jan 01 2016
Journal Name
مجلة المستنصرية للعلوم والتربية
Calculation of Electron Drift Velocity in Xenon Gas Using Boltzmann Equation Analysis
...Show More Authors

Publication Date
Mon Jun 05 2023
Journal Name
Al-khwarizmi Engineering Journal
Fabrication and Analysis of Denture Plate Using Single Point Incremental Sheet Forming
...Show More Authors

Incremental sheet forming (ISF) is a metal forming technology in which small incremental deformations determine the final shape. The sheet is deformed by a hemispherical tool that follows the required shape contour to deform the sheet into the desired geometry. In this study, single point incremental sheet forming (SPIF) has been implemented in dentistry to manufacture a denture plate using two types of stainless steel, 304 and 316L, with an initial thickness of 0.5mm and 0.8mm, respectively. Stainless steel was selected due to its biocompatibility and reasonable cost. A three-dimensional (3D) analysis procedure was conducted to evaluate the manufactured part's geometrical accuracy and thickness distribution. The obtained results confirm

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (2)
Scopus Crossref
Publication Date
Tue Oct 01 2024
Journal Name
Mathematics For Applications
DIRICHLET PROCESS ANALYSIS USING BIORTHOGONAL WAVELET: A STATISTICAL STUDY OF FINANCIAL MARKET
...Show More Authors

The Dirichlet process is an important fundamental object in nonparametric Bayesian modelling, applied to a wide range of problems in machine learning, statistics, and bioinformatics, among other fields. This flexible stochastic process models rich data structures with unknown or evolving number of clusters. It is a valuable tool for encoding the true complexity of real-world data in computer models. Our results show that the Dirichlet process improves, both in distribution density and in signal-to-noise ratio, with larger sample size; achieves slow decay rate to its base distribution; has improved convergence and stability; and thrives with a Gaussian base distribution, which is much better than the Gamma distribution. The performance depen

... Show More
View Publication
Scopus
Publication Date
Fri Nov 01 2019
Journal Name
Journal Of Engineering
Analysis of Shell and Double Concentric Tube Heat Exchanger Using CFD Application
...Show More Authors

This study focuses on CFD analysis in the field of the shell and double concentric tube heat exchanger. A commercial CFD package was used to resolve the flow and temperature fields inside the shell and tubes of the heat exchanger used. Simulations by CFD are performed for the single shell and double concentric tube.

This heat exchanger included 16 tubes and 20 baffles. The shell had a length of 1.18 m and its diameter was 220 mm. Solid Works 2014, ANSYS 15.0 software was used to analyze the fields of flow and temperature inside the shell and the tubes. The RNG k-ε model was used and it provided good results. Coarse and fine meshes were investigated, showing that aspect ratio has no significant effect. 14 million

... Show More
View Publication Preview PDF
Crossref (4)
Crossref