Preferred Language
Articles
/
axcDWJIBVTCNdQwCFqys
Design and Implementation of a Microstrip Six-Port Reflectometer (SPR) with Enhanced Bandwidth
...Show More Authors

A compact microstrip six-port reflectometer (SPR) with extended bandwidth is proposed in this paper. The design is based on using 16-dB multi-section coupled line directional couplers and a multi-section 3-dB Wilkinson power divider operating from 1 to 6 GHz. The proposed SPR employs only two calibration standards: a matched load and an open load. As compared to other dielectric substrates, fabricating the proposed SPR involves using a low-cost (FR4) substrate. A novel algorithm is also proposed to estimate the complex reflection coefficient over the frequency ranges at which the standard performance of the circuit components is not fully satisfied. The new algorithm is based on the circles’ intersection points, which have been derived from basic SPR equations, to estimate the complex reflection coefficient. To validate the SPR performance, a multiband microstrip patch antenna has been measured and the resulted reflection coefficient is compared with those obtained using a vector network analyzer (VNA). Results show that the proposed SPR provides a good estimation of the complex reflection coefficient within the frequency range of 1 GHz to 8 GHz. Owing to its compact size and ease of fabrication, the proposed reflectometer is suitable for various microwave broadband applications.

Crossref
View Publication
Publication Date
Fri Oct 03 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Assessment of tongue space area in a sample of Iraqi adults with class I dental and skeletal pattern
...Show More Authors

Background: Lateral cephalometric radiography is commonly used as a standard tool in orthodontic assessment and treatment planning. This study aimed to determine the tongue and surrounding space area in a sample of Iraqi adults with class I dental and skeletal pattern. Materials and methods: The study included thirty healthy subjects (15 males and 15 females) with an age ranged between 23-34 years and class I dental and skeletal pattern with no history of any sleep related disorders. The assessed cephalometric measurement included length and height of the tongue and position of hyoid bone from cervical line. Descriptive statistics were obtained for the data. Genders difference was evaluated by independent sample t-test. Results: There wer

... Show More
View Publication Preview PDF
Publication Date
Fri Mar 10 2023
Journal Name
Aspac J. Mol. Biol. Biotechnol
Influence of IL-28B serum level and gene polymorphism in a sample of Iraqi patients with ankylosing spondylitis
...Show More Authors

Ankylosing spondylitis (AS) represents one kind of advanced arthritis formed via inflammatory stimuli long-term in the spin‘s joints. Interleukin (IL)-29 (interferon- lambda1(IFN- λ1)), interleukin (IL)-28A (interferon- lambda 2 (IFN- λ2)) and interleukin (IL)-28B (interferon- lambda 3(IFN-λ3)) are three interferon lambda (IFN- λs) molecules that have recently been identified as new members of the IFN family. IL-28B expression in ankylosing spondylitis (AS) is not well understood. 150 male healthy controls ((HC) and 160 males with AS as patients group participated in this study. Serum level and gene polymorphism were assessed using an enzyme-linked immunosorbent assay and Sanger sequencing for IL-28B, respectively. The results showed

... Show More
Publication Date
Tue Dec 24 2024
Journal Name
Malaysian Journal Of Mathematical Sciences
Exploring the Role of Hunting Cooperation, and Fear in a Prey-Predator Model with Two Age Stages
...Show More Authors

The aim of this study is to utilize the behavior of a mathematical model consisting of three-species with Lotka Volterra functional response with incorporating of fear and hunting cooperation factors with both juvenile and adult predators. The existence of equilibrium points of the system was discussed the conditions with variables. The behavior of model referred by local stability in nearness of any an equilibrium point and the conditions for the method of approximating the solution has been studied locally. We define a suitable Lyapunov function that covers every element of the nonlinear system and illustrate that it works. The effect of the death factor was observed in some periods, leading to non-stability. To confirm the theore

... Show More
View Publication
Clarivate Crossref
Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
Exploring the Challenges of Diagnosing Thyroid Disease with Imbalanced Data and Machine Learning: A Systematic Literature Review
...Show More Authors

Thyroid disease is a common disease affecting millions worldwide. Early diagnosis and treatment of thyroid disease can help prevent more serious complications and improve long-term health outcomes. However, thyroid disease diagnosis can be challenging due to its variable symptoms and limited diagnostic tests. By processing enormous amounts of data and seeing trends that may not be immediately evident to human doctors, Machine Learning (ML) algorithms may be capable of increasing the accuracy with which thyroid disease is diagnosed. This study seeks to discover the most recent ML-based and data-driven developments and strategies for diagnosing thyroid disease while considering the challenges associated with imbalanced data in thyroid dise

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Engineering
Outdoor Testing of a Zig-Zag Solar Air heater with and without Artificial Roughness on Absorber Plate
...Show More Authors

In this paper, thermal performance of a zig-zig solar air heater (ZZSAH) with and without using steel wire mesh on the absorber plate of the collector is experimentally investigated. The experimental work includes four inclination angles of the collector 20o, 30o, 45o, and 60o and four air mass flow rates of 0.03, 0.04, 0.06, and 0.08 kg/s under varieties of operating conditions of a geographic location of  Baghdad. New correlation equations of Nusselt number are obtained from experimental results for both types of collectors where the effect of varying of the inclination angle of collector taken into consideration in the experiment. The correlations show good agreement wi

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Mon Aug 01 2011
Journal Name
Journal Of Engineering
EXPERIMENTAL INVESTIGATION OF LAMINAR NATURAL CONVECTION HEAT TRANSFER IN A RECTANGULAR ENCLOSURE WITH AND WITHOUT INSIDE PARTITIONS
...Show More Authors

Experimental study has been conducted for laminar natural convection heat transfer of air flow through a rectangular enclosure fitted with vertical partition. The partition was oriented parallel to the two vertical isothermal walls with different temperatures, while all the other surfaces of the enclosure were insulated. In this study a test rig has been designed and constructed to allow studying the effect of Rayleigh number, aperture height ratio, partition thickness, the position of aperture according to the side walls and according to the height, the position of the partition according to the hot wall, and partition inclination. The experiments were carried out with air as the working fluid for Rayleigh number range (5*107 – 1.3*10

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Nov 28 2016
Journal Name
Separation Science And Technology
Using sewage sludge as a permeable reactive barrier for remediation of groundwater contaminated with lead and phenol
...Show More Authors

Scopus (24)
Crossref (24)
Scopus Clarivate Crossref
Publication Date
Mon Jan 01 2024
Journal Name
Wiadomości Lekarskie
Evaluation of clinical and demographical finding in patients with oral lichen planus: A retrospective cross sectional study
...Show More Authors

Aim: To learn more about Oral Lichen Planus Iraqi patients, including their background information, symptoms, and prognosis. Materials and Methods: From the Oral and Maxillofacial Pathology Department, College of Dentistry, Baghdad University, we retrospectively reviewed the medical records of 68 patients with a histologically confirmed clinical diagnosis of oral lichen planus and subsequently contacted the patients by phone to evaluate their prognosis. Results: Females were more likely than males to experience severe pain; the reticular form of Oral Lichen Planus was the most prevalent at 38.2%, but the erosive type was more prevalent among females. Only 53 of 68 patients responded to phone calls. More than 37% of those respondents reporte

... Show More
View Publication
Scopus (1)
Scopus Crossref
Publication Date
Fri Oct 03 2025
Journal Name
Journal Of Stomatology
Association of modifiable and non-modifiable risk factors with periodontal disease in Iraqi individuals: a retrospective study
...Show More Authors

Introduction Periodontal diseases are ranked among the most common health problems affecting mankind. These conditions are initiated by bacterial biofilm, which is further modulated by several risk factors. Objectives To investigate the association of different risk factors with periodontal...

View Publication Preview PDF
Publication Date
Thu Dec 14 2023
Journal Name
4th International Conference Of Modern Technologies In Agricultural Sciences
A study of the Effect of Diesel Oil Contamination with Glycol on the Performance of a Diesel Engine
...Show More Authors

The performance of a diesel engine was tested with diesel oil contaminated with glycol at the engineering workshop/Department of Agricultural Machines and Equipment / College of the Agricultural Engineering Sciences at the University of Baghdad. To investigate the impact of different concentrations of glycol on the performance of a diesel engine, an experimental water-cooled four-stroke motor was utilized, with oil containing 0, 100, and 200 parts per million (ppm). Specific fuel consumption, thermal efficiency, friction power, and exhaust gas temperature were examined as performance indicators. To compare the significance of the treatments, the study employed a full randomization design (CRD), with three replicates for each treatment at th

... Show More