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Challenges and limits of fractal and slot antennas for WLAN, LTE, ISM, and 5G communication: a review paper
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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.

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Publication Date
Fri Dec 08 2023
Journal Name
Iraqi Journal Of Science
A Modified Hestenes-Stiefel Conjugate Gradient Method and its Global convergence for unconstrained optimization
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In this paper, we proposed a modified Hestenes-Stiefel (HS) conjugate
gradient method. This achieves a high order accuracy in approximating the second
order curvature information of the objective function by utilizing the modified
secant condition which is proposed by Babaie-Kafaki [1], also we derive a nonquadratic
conjugate gradient model. The important property of the suggestion
method that is satisfy the descent property and global convergence independent of
the accuracy of the line search. In addition, we prove the global convergence under
some suitable conditions, and we reported the numerical results under these
conditions.

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Publication Date
Mon Aug 01 2022
Journal Name
Journal Of Structural Engineering
Standard Pushout Tests and Design Rules for a Bolted–Welded Hybrid Demountable Shear Connector
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A bolted–welded hybrid demountable shear connector for use in deconstructable steel–concrete composite buildings and bridges was proposed. The hybrid connector consisted of a partially threaded stud, which was welded on the flange of a steel section, and a machined steel tube with compatible geometry, which was bolted on the stud. Four standard pushout tests according to Eurocode 4 were carried out to assess the shear performance of the hybrid connector. The experimental results show that the initial stiffness, shear resistance, and slip capacity of the proposed connector were higher than those of traditional welded studs. The hybrid connector was a ductile connector, according to Eurocode 4, with slip capacity higher than 6 mm. A nonli

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Publication Date
Sun Jan 01 2023
Journal Name
Isvs E-journal
Preserving the Past and Building the Future: A Sustainable Urban Plan for Mosul, Iraq
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Preserving the Past and Building the Future: A Sustainable Urban Plan for Mosul, Iraq

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Scopus
Publication Date
Tue Dec 12 2017
Journal Name
Al-khwarizmi Engineering Journal
Design a Vegetative Filter Strips Length Using VFSMOD_W Model for Reducing Sediments and Pesticides
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 Abstract 

The vegetative filter strips (VFS) are a useful tool used for reducing the movement of sediment and pesticide in therivers. The filter strip’s soil can help in reducing the runoff volume by infiltration. However, the characteristics of VFS (i.e., length) are not recently identified depending on the estimation of VFS modeling performance. The aim of this research is to study these characteristics and determine acorrelation between filter strip length and percent reduction (trapping efficiency) for sediment, water, and pesticide. Two proposed pesticides(one has organic carbon sorption coefficient, Koc, of 147 L/kg which is more moveable than XXXX, and another one

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Publication Date
Mon Jan 01 2024
Journal Name
Aip Conference Proceedings
ZnO: MWCNT optical hybrid filter a promising nanomaterial for wastewater treatment and antimicrobial applications
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Publication Date
Wed Jul 01 2015
Journal Name
Al–bahith Al–a'alami
The Role of Communication Methods in Changing the Values of the Urban Family
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This article discusses the change of values in urban family, because of various communication media and modern technologies as one of the most important factors affecting the changing family values in urban areas, this means becoming part of urban life. And focuses on the family in urban areas, for the privacy of the social, economic, demographic and cultural help to this effect, and because cities are the most friction and interaction with modern technologies.

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Publication Date
Sun May 17 2020
Journal Name
Iraqi Journal Of Science
On Existence and Uniqueness of an Integrable Solution for a Fractional Volterra Integral Equation on 𝑹+
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In this paper, by using the Banach fixed point theorem, we prove the existence and uniqueness theorem of a fractional Volterra integral equation in the space of Lebesgue integrable 𝐿1(𝑅+) on unbounded interval [0,∞).

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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Engineering
The The Use of Copper and Aluminum Electrodes for Energy Production in a Microbial Fuel Cell
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Microbial fuel cell is a device that uses the microorganism metabolism for the production of electricity under specific operating conditions. Double chamber microbial fuel cell was tested for the use of two cheap electrode materials copper and aluminum for the production of electricity under different operating conditions. The investigated conditions were concentration of microorganism (yeast) (0.5- 2 g/l), solutions temperature (33-45 oC) and concentration of glucose as a substrate (1.5- 6 g/l). The results demonstrated that copper electrode exhibit good performance while the performance of aluminum is poor. The electricity is generated with and without the addition of substrate. Addition of glucose substrate

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Publication Date
Wed Feb 05 2025
Journal Name
Al–bahith Al–a'alami
HUMAN MODELING IN THE IRAQI PRESS: (A Survey of Human Modeling for March And April 2011)
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This research deals with what so called concept of The Human Model and how Iraqi Media concerns of this concept practically as it plays a key role in attracting readers, on the first hand. On the second, it is important to shed light on the scientific desire of the Iraqi Media and how it deals with this contemporary trend especially in editorial media.

The importance of the research stems from the fact that it alerts to a new stream of modern trends in journalistic writing, according to many modern Arab and foreign media studies; and to the importance of employing human modeling in dealing with facts, events, issues and problems in various editorial arts within their effective influence in concilia

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Crossref
Publication Date
Thu Mar 09 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis, Spectroscopic and Adsorption Studies of Cobalt (II) Complex for a ligand β-enaminone Derived from
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   This paper concerns is the preparation and characterization of a bidentate ligand [4-(5,5dimethyl-3-oxocyclohex-1-enylamino)-N-(5-methylisoxazol-3-yl) benzene sulfonamide].  The ligand was prepared from fusing of sulfamethoxazole and dimedone at (140) ºC for half hour.              The complex was prepared by refluxing the ligand with a bivalent cobalt ion using ethanol as a solvent. The prepared ligand and complex were identified using Spectroscopic methods. The proposed tetrahedral geometry around the metal ions studied were concluded from these measurements. Both molar ratio and continuous variation method were studied to determine metal to ligand ratio (M:L). The M to L ratio wa

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