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
Mon Nov 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
The Impact Of Adopting The Social Responsibility On Marketing Performance An Applied Study on NAFTAL Company
...Show More Authors

This research paper aims at studying the effect of adopting the corporate social responsibility on marketing performance indicators, where the study adopted the descriptive method for theoretical concepts, in addition to the statistical approach by using the SPSS v25 program to analyze the questionnaire and test the hypotheses of the study. The results showed that there is a positive correlation between social responsibility and marketing performance indicators, and the study found that it is better for NAFTAL Company to mix the environmental and social responsibilities in order to improve its marketing performance. Also, the study recommended that Naftal should adopt the four responsibilities equally, correctly and make its work

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 01 2020
Journal Name
Astrophysics And Space Science
The compound stream event of March 20-25, 2011 as measured by the STEREO B spacecraft
...Show More Authors
Abstract<p>The interaction of interplanetary coronal mass ejections (ICME) with each other and with co-rotating interaction regions (CIR) changes their configuration, dynamics, magnetic field and plasma characteristics and can make space weather forecasting difficult. During the period of March 20–25, 2011, the Solar Terrestrial Relation Observatory (<italic>STEREO</italic> B) encountered a compound stream containing several interacting structures. Our analysis suggests that the stream consists of two ICMEs followed by an embedded ICME/CIR. The sudden appearance of the third ICME within the fast wind side of the CIR causes the proton temperature(<inline-formula><alternatives><tex-math></tex-math></alternatives></inline-formula></p> ... Show More
View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Wed Mar 02 2022
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Numbered Heads Strategy on Developing Oral Expression Skills among Fifth-Grade Primary Students
...Show More Authors

This research aims to identify the effect of numbered heads strategy on developing oral expression skills among fifth-grade primary students in Bisha Province. To achieve this, the researcher prepared a research tool represented in the observation card which consists of (27) statements distributed in four axes. The tool was sent to (5) experts in the field to verify their validity. In light of their corrections, the tool was developed to be valid for gathering field information. To verify the validity of the content and the reliability of the tool, the researcher applied it to a sample consists of (20) students from outside the research group. The overall coefficient of correlation between the statements of the tool is as follows: (.95,

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 01 2018
Journal Name
Journal Of Educational And Psychological Researches
Educational research obstacles as perceived by academic faculty members in the south universities of west bank
...Show More Authors

The study aims to identify the educational research obstacles as perceived by the faculty members at the universities of south in the west bank. As for study population, it included all (60) faculty-member in the colleges of education (bait lahem, alahliyah, al-khalil, and al-Quds almaftoha). To collect study data, the researcher used a questionnaire that consisted of (43) item; it has categorized into seven-domains: academic working conditions, academic management, resources and information, faculty members, publication, planning, and funding educational research. The findings revealed that Educational research obstacles were high with an average of (4, 39), no significant differences among sample averages and stander deviations on the

... Show More
View Publication Preview PDF
Publication Date
Mon Jun 01 2015
Journal Name
Journal Of Engineering
Artificial Neural Networks Modeling of Total Dissolved Solid in the Selected Locations on Tigris River, Iraq
...Show More Authors

The study aims to predict Total Dissolved Solids (TDS) as a water quality indicator parameter at spatial and temporal distribution of the Tigris River, Iraq by using Artificial Neural Network (ANN) model. This study was conducted on this river between Mosul and Amarah in Iraq on five positions stretching along the river for the period from 2001to 2011. In the ANNs model calibration, a computer program of multiple linear regressions is used to obtain a set of coefficient for a linear model. The input parameters of the ANNs model were the discharge of the Tigris River, the year, the month and the distance of the sampling stations from upstream of the river. The sensitivity analysis indicated that the distance and discharge

... Show More
View Publication Preview PDF
Publication Date
Wed Sep 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Significance of Salivary miRNA 21 Determined by Real Time PCR in Patients with Squamous Cell Carcinoma
...Show More Authors

Background: Salivary biomarkers, a non-invasive alternative method to serum and tissue based biomarkers and it is consider as an effective modality for early diagnosis. Salivary microRNA 21, a nucleotide biomarker, was reported to increase in patients with oral squamous cell carcinoma. This study was conducted to measure the fold change of microRNA 21 in stimulated saliva and to study its association with smoking and occurrence of oral squamous cell carcinoma. Materials and methods: A 20 patients with oral squamous cell carcinoma who used to be smokers was included in addition to 40 control subjects (20 smokers and 20 non- smokers health looking subjects). Stimulated saliva was collected under standardized condition. Salivary microRNA 21 wa

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Tue Jun 01 2021
Journal Name
Baghdad Science Journal
The Prevalence of Parasites in the Domestic Pigeons (Columba livia domestica) in Zakho City, Kurdistan-Iraq
...Show More Authors

Pigeons have accompanied humans since ancient time because they are used as a source of food, pets, hobby, and religious symbols. Pigeons have shown high prevalence rate of infection with gastrointestinal helminths and protozoan. This study was conducted to evaluate the prevalence of parasitic infections in the domestic pigeon (Columba livia domestica) from October, 2017 to April, 2018, purchased from bird market of Zakho City, Kurdistan region. The samples were taken from 50 adult pigeons (28 males and 22 females). The birds were transferred to Parasitology Laboratory, Faculty of Science, Zakho University. In the laboratory, each bird was sacrificed and immediately the feather and skin of under wings, chest and the rest of the

... Show More
View Publication Preview PDF
Scopus Clarivate Crossref
Publication Date
Fri Dec 30 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Well Performance Following Matrix Acidizing Treatment: Case Study of the Mi4 Unit in Ahdeb Oil Field
...Show More Authors

The productivity of oil wells may be improved by determining the value of enhancing well productivity and the likely reasons or sources of formation damage after the well has been recognized as underperforming. Oil well productivity may be improved, but the economics of this gradual improvement may be compromised. It is important to analyze the influence of the skin effect on the recovery of the reserve.    The acid treatment evaluated for the well AD-12, primarily for the zone Mi4;  using a license of Stimpro Stimulation Software to validate the experimental work to the field scale, this software is considered the most comprehensive instrument for planning and monitoring matrix acid treatments and utilizing actual data to provide a far

... Show More
Crossref (3)
Crossref
Publication Date
Tue Sep 01 2020
Journal Name
Baghdad Science Journal
Decolorization of Phenol Red Dye by Immobilized Laccase in Chitosan Beads Using Laccase - Mediator - System Model
...Show More Authors

This work describes the enhancement of phenol red decolorization through immobilizing of laccase in chitosan and enzyme recycling. Commercial laccase from white rot fungus, Trametesversicolor (Tvlac), was immobilizedin to freshly prepared chitosan beads by using glutaraldehyde as a cross linker. Characterization of prepared chitosan was confirmed by FTIR and scanning electron microscope (SEM). Tvlac (46.2 U/mL) immobilized into chitosan beads at 0.8 % glutaraldehyde (v/v) within 24 hrs. Synthetic (HBT) and natural (vanillin) mediators were used to enhance dye decolorizoation. It was found that 89 % of phenol red was decolorized by chitosan beads within 180 min. in the absence of enzyme and mediator, while decolorization percenta

... Show More
View Publication Preview PDF
Scopus (11)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Sun Jul 21 2024
Journal Name
Cureus
The Effect of Maternal Blood Glucose on Umbilical Cord Blood Fibrinogen in Women With Gestational Diabetes
...Show More Authors

Preview PDF