Preferred Language
Articles
/
-xc_kJMBVTCNdQwC1NXk
Challenges and limits of fractal and slot antennas for WLAN, LTE, ISM, and 5G communication: a review paper
...Show More Authors

Abstract Portable communication devices such as WLAN, WiMAX, LTE, ISM, and 5G utilize one or more of the triple bands at (2.32.7 GHz,3.4–3.6GHz,and5–6GHz)andsufferfromtheeffectofmultipathproblemsbecausetheyareusedinurbanregions.To date, no one has performed a review of the antennas used for these types of wireless communications. This study reviewed two types of microstrip antennas (slot and fractal) that have been reported by researchers (as a single element) using a survey that included the evaluation of several important specifications of the antennas in previous research, such as operating bandwidth, gain, efficiency, axial ratio bandwidth (ARBW), and size. The weaknesses in the design of all antennas were carefully identified to determine the most important challenges in the design of these antennas and name the most important limits in the design to be overcome in future research. This study also indicated some antennas that have circular polarization characteristics, the techniques used to generate the circular polarization characteristics, and the challenges. Finally, several suggestions as a guideline for antenna design and future work in designing antennas for Wi-Fi, LTE, and WiMAX communications, according to the market demands, and methods for overcoming the identified limits are presented.

Scopus Clarivate Crossref
View Publication
Publication Date
Thu Oct 01 2009
Journal Name
Iraqi Journal Of Physics
The Structural and Optical Properties of Hydrogenated and Nitrogenated a-Si0.1Ge0.9 and a-Si0.1Ge0.9:3% B Thin Films
...Show More Authors

It is shown that pure and 3% boron doped a-Si0.1Ge0.9:H and a-Si0.1Ge0.9:N thin films
could be prepared by flash evaporation processes. The hydrogenation and nitrogenation
are very successful in situ after depositing the films. The FT-IR analysis gave all the
known absorbing bonds of hydrogen and nitrogen with Si and Ge.
Our data showed a considerable effect of annealing temperature on the structural and
optical properties of the prepared films. The optical energy gap (Eopt.) of a-Si0.1Ge0.9
samples showed to have significant increase with annealing temperature (Ta) also the
refractive index and the real part of dielectric constant increases with Ta, however the
extinction coefficient and imaginary part of dielect

... Show More
View Publication Preview PDF
Publication Date
Fri Feb 17 2023
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn: 2789-3219 )
The Association of Genetic Polymorphisms in Tumor Necrosis Factor-Alpha and Interleukins with Disease Severity or Response to Biological Therapy in Iraqi Rheumatoid Arthritis Patients: A Narrative Review
...Show More Authors

Background: Tumor necrosis factor-alpha (TNF-α) and interleukins play important roles in the pathogenesis of rheumatoid arthritis (RA). Genetic research has been employed to find many of the missing connections between genetic risk variations and causal genetic components. Objective: The goal of this study is to look at the genetic variations of TNF-α and interleukins in Iraqi RA patients and see how they relate to disease severity or response to biological therapy. Method: Using specific keywords, the authors conducted a systematic and comprehensive search to identify relevant Iraqi studies examining the genetic variations of TNF-α and interleukins in Iraqi RA patients and how they relate to disease severity or response to biolo

... Show More
View Publication Preview PDF
Scopus (3)
Crossref (4)
Scopus Crossref
Publication Date
Thu Oct 01 2020
Journal Name
Ore Geology Reviews
Book review
...Show More Authors

View Publication
Clarivate Crossref
Publication Date
Tue Dec 07 2021
Design and numerical verification of a polarization-independent grating coupler using a double-layer approach for visible wavelengths applications
...Show More Authors

View Publication
Scopus (1)
Scopus Clarivate Crossref
Publication Date
Wed Jan 01 2014
Journal Name
Scienceasia
A combined compact genetic algorithm and local search method for optimizing the ARMA(1,1) model of a likelihood estimator
...Show More Authors

In this paper, a compact genetic algorithm (CGA) is enhanced by integrating its selection strategy with a steepest descent algorithm (SDA) as a local search method to give I-CGA-SDA. This system is an attempt to avoid the large CPU time and computational complexity of the standard genetic algorithm. Here, CGA dramatically reduces the number of bits required to store the population and has a faster convergence. Consequently, this integrated system is used to optimize the maximum likelihood function lnL(φ1, θ1) of the mixed model. Simulation results based on MSE were compared with those obtained from the SDA and showed that the hybrid genetic algorithm (HGA) and I-CGA-SDA can give a good estimator of (φ1, θ1) for the ARMA(1,1) model. Anot

... Show More
View Publication
Scopus (3)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Wed Jul 27 2022
Journal Name
Journal Of Chemical Technology & Biotechnology
Broad‐ranging review: configurations, membrane types, governing equations, and influencing factors on microbial desalination cell technology
...Show More Authors
Abstract<p>Seawater might serve as a fresh‐water supply for future generations to help meet the growing need for clean drinking water. Desalination and waste management using newer and more energy intensive processes are not viable options in the long term. Thus, an integrated and sustainable strategy is required to accomplish cost‐effective desalination via wastewater treatment. A microbial desalination cell (MDC) is a new technology that can treat wastewater, desalinate saltwater, and produce green energy simultaneously. Bio‐electrochemical oxidation of wastewater organics creates power using this method. Desalination and the creation of value‐added by‐products are expected because of this ionic mov</p> ... Show More
View Publication
Scopus (16)
Crossref (13)
Scopus Clarivate Crossref
Publication Date
Wed Oct 01 2014
Journal Name
Al–bahith Al–a'alami
Demonstrators' slogans in Tahrir square (Analytical study of the communication message)
...Show More Authors

The research entitled "The Slogans of Demonstrators at Al-Tahreer Square – analytical study for communicative letters" studies the slogans of demonstrators as a communicative means having many signs reflecting the political, social, cultural relations exist in the minds of people. It is so easy to understand its meaning, examining its goals; and explaining their meanings. For these reasons, we have chosen such a topic. Since the means of communications transfer letters between a sender and receiver, the importance of this research is that it is a researchable trial to acknowledge the issues behind the demonstrators' slogans and the different styles have been chosen by them for a whole year; the different sides of the demonstration sinc

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Oct 01 2020
Journal Name
Heliyon
Inter-personal versus content: assessment of communication skills in Iraqi physicians
...Show More Authors

View Publication
Scopus (3)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Thu Oct 18 2018
Journal Name
European Journal Of Organic Chemistry
PdII-Mediated Oxidative Amination for Access to a 9-Azabicyclo[4.2.1]nonane Compound Library and Anatoxin-a
...Show More Authors

View Publication Preview PDF
Crossref (4)
Clarivate Crossref
Publication Date
Mon Nov 01 2021
Journal Name
Journal Of Engineering
Study of Using of Recycled Brick Waste (RBW) to produce Environmental Friendly Concrete: A Review
...Show More Authors

Several million tons of solid waste are produced each year as a result of construction and demolition activities around the world, and brick waste is one of the most widely wastes. Recently, there has been growing number in studies that conducted on using of recycling brick waste (RBW) to produce environmentally friendly concrete. The use of brick waste (BW) as potential partial cement or aggregate replacement materials is summarized in this review where the performance is discussed in the form of the mechanical strength and properties that related to durability of  concrete. It was found that, because the pozzolanic activity of clay brick powder, it can be utilized as substitute for cement in replacement level up t

... Show More
View Publication Preview PDF
Crossref (5)
Crossref