Preferred Language
Articles
/
ZxbnBYcBVTCNdQwCKC_T
The Role of Correlation in the Performance of Massive MIMO Systems
...Show More Authors

Massive multiple-input multiple-output (m-MIMO) is considered as an essential technique to meet the high data rate requirements of future sixth generation (6G) wireless communications networks. The vast majority of m-MIMO research has assumed that the channels are uncorrelated. However, this assumption seems highly idealistic. Therefore, this study investigates the m-MIMO performance when the channels are correlated and the base station employs different antenna array topologies, namely the uniform linear array (ULA) and uniform rectangular array (URA). In addition, this study develops analyses of the mean square error (MSE) and the regularized zero-forcing (RZF) precoder under imperfect channel state information (CSI) and a realistic physical channel model. To this end, the MSE minimization and the spectral efficiency (SE) maximization are investigated. The results show that the SE is significantly degraded using the URA topology even when the RZF precoder is used. This is because the level of interference is significantly increased in the highly correlated channels even though the MSE is considerably minimized. This implies that using a URA topology with relatively high channel correlations would not be beneficial to the SE unless an interference management scheme is exploited.

Scopus Clarivate Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Jan 02 2017
Journal Name
Journal Of Educational And Psychological Researches
The effectiveness of the structural model of learning in the acquisition of geographical concepts among students of the first grade average)
...Show More Authors

The current research aims to find out ( the effectiveness of the structural model of learning in the acquisition of geographical concepts at the first grade average students ) , and achieving the goals of research has been formulating the null hypothesis of the following :

    " There is no difference statistically significant when Mistoi (0.5 ) between the mean scores of the collection of students in the experimental group that is studying the general geographical principles " Bonmozj constructivist learning " and the mean scores of the control group , which is considering the same article ," the traditional way " to acquire concepts.

The researcher adopted th

... Show More
View Publication Preview PDF
Publication Date
Sat Oct 01 2022
Journal Name
Al–bahith Al–a'alami
The evolution of the press image in the Iraqi press (An analytical study of the pictures of the first page of Al-Sabah newspaper for the year)
...Show More Authors

This research sheds light on the development that has occurred on the use of press pictures in the Iraqi press by analyzing the form and content of the images used in (Al-Sabaah) newspaper for the 2012 model. The researcher's interest in this topic for what represented by the press picture of a way to highlight and attract the reader's attention to the substance journalist who represents the goals behind the newspaper publishing.

This research is divided into three sections. The first one dealt with the methodological framework of the research, and the second part addressed the aspect of press pictures and its history and technological development, while the third section devoted to the study of the development of the form and co

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Jun 30 2013
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Zinc Element Traces to Inhibit Scale Formation on Cooling Tower and Air Cooler Systems
...Show More Authors

Calcium carbonate is predominantly present in aqueous systems, which is
commonly used in industrial processes. It has inverse solubility characteristics
resulting in the deposition of scale on heat transfer surface. This paper focuses on
developing methods for inhibition of calcium carbonate scale formation in cooling
tower and air cooler system where scaling can cause serious problems, ZnCl 2 and ZnI
2 has been investigated as scale inhibitor on AISI 316 and 304. ZnCl 2 were more
effective than ZnI 2 in both systems, and AISI 316 show more receptivity to the
chlorides salt compared to AISI 304. The inhibitors were more effective in cooling
tower than air cooler system. AISI 316 show more constant inhibition effic

... Show More
View Publication Preview PDF
Publication Date
Thu Jun 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Semiparametric Bayesian Method with Classical Method for Estimating Systems Reliability using Simulation Procedure
...Show More Authors

               In this research, the semiparametric Bayesian method is compared with the classical  method to  estimate reliability function of three  systems :  k-out of-n system, series system, and parallel system. Each system consists of three components, the first one represents the composite parametric in which failure times distributed as exponential, whereas the second and the third components are nonparametric ones in which reliability estimations depend on Kernel method using two methods to estimate bandwidth parameter h method and Kaplan-Meier method. To indicate a better method for system reliability function estimation, it has be

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Dec 01 2020
Journal Name
Baghdad Science Journal
Emergency Messages Dissemination Challenges Through Connected Vehicles for Efficient Intelligent Transportation Systems: A Review
...Show More Authors

Recent growth in transport and wireless communication technologies has aided the evolution of Intelligent Transportation Systems (ITS). The ITS is based on different types of transportation modes like road, rail, ocean and aviation. Vehicular ad hoc network (VANET) is a technology that considers moving vehicles as nodes in a network to create a wireless communication network. VANET has emerged as a resourceful approach to enhance the road safety. Road safety has become a critical issue in recent years. Emergency incidents such as accidents, heavy traffic and road damages are the main causes of the inefficiency of the traffic flow. These occurrences do not only create the congestion on the road but also increase the fuel consumption and p

... Show More
View Publication Preview PDF
Scopus (4)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Tue Mar 26 2024
Journal Name
World Electric Vehicle Journal
Fast Finite-Time Composite Controller for Vehicle Steer-by-Wire Systems with Communication Delays
...Show More Authors

The modern steer-by-wire (SBW) systems represent a revolutionary departure from traditional automotive designs, replacing mechanical linkages with electronic control mechanisms. However, the integration of such cutting-edge technologies is not without its challenges, and one critical aspect that demands thorough consideration is the presence of nonlinear dynamics and communication network time delays. Therefore, to handle the tracking error caused by the challenge of time delays and to overcome the parameter uncertainties and external perturbations, a robust fast finite-time composite controller (FFTCC) is proposed for improving the performance and safety of the SBW systems in the present article. By lumping the uncertainties, parameter var

... Show More
View Publication
Scopus (5)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Mon Apr 17 2017
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
THE POSSIBILITY OF THE APPLICATION OF ENVIRONMENTAL FINES TO REDUCE THE WASTE GENERATED FROM THE SHOPE AND RESTAURANTS IN THE CITY OF BAGHDAD/ CASE STUDY.: THE POSSIBILITY OF THE APPLICATION OF ENVIRONMENTAL FINES TO REDUCE THE WASTE GENERATED FROM THE SHOPE AND RESTAURANTS IN THE CITY OF BAGHDAD/ CASE STUDY.
...Show More Authors

The research aims to identify the possibility of applying environmental fines to commercial shops and restaurants to reduce the environmental pollution represented by the wastes generated from them. The research sample was divided into two groups, including the first (20) commercial shops (meat shops and slaughter it, fruits & vegetables, legumes and accessories) and second (30) Restaurant in the city of Baghdad on both sides of Karkh and Rusafa. The quality of the waste was classified into carton, plastic, aluminum, glass, paper, cork and food waste. The study revealed the possibility of applying environmental fines to restaurants and shops to reduce the waste generated from them throughout the year and to apply continuous monitorin

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2023
Journal Name
Saudi Endodontic Journal
Comparison of root canal transportation and centering after instrumentation through conservative and traditional access cavities using different file systems
...Show More Authors
Introduction:

While conservative access preparations could increase fracture resistance of endodontically treated teeth, it may influence the shape of the prepared root canal. The aim of this study was to compare the prepared canal transportation and centering ability after continuous rotation or reciprocation instrumentation in teeth accessed through traditional or conservative endodontic cavities by using cone-beam computed tomography (CBCT).

Materials and Methods:

Forty extracted intact, matured, and 2-rooted human maxillary first premolars were selected for this

... Show More
View Publication
Scopus (6)
Crossref (7)
Scopus Crossref
Publication Date
Fri Mar 10 2017
Journal Name
Superconductor Science And Technology
Conceptual designs of conduction cooled MgB<sub>2</sub> magnets for 1.5 and 3.0 T full body MRI systems
...Show More Authors

View Publication
Scopus (61)
Crossref (58)
Scopus Clarivate Crossref
Publication Date
Wed Apr 29 2020
Journal Name
Indian Journal Of Forensic Medicine & Toxicology
Cyclic Fatigue Resistance of Wave One Gold, F6 SkyTaper, One Curve, and AF Blue R3 NiTi Rotary Instrumentation Systems
...Show More Authors

Objective: This in vitro study is aimed to compare and evaluate the cyclic fatigue of four varying NiTi rotary instrumentation systems. Method: In this study, four types of rotary files were used in four groups (10 files for each group), namely, Group A: Wave One Gold; Group B: AF Blue R3; Group C: One Curve; Group D: F6 SkyTaper. These groups were evaluated by a cyclic fatigue apparatus to measure cyclic fatigue resistance within the artificial metallic simulating canal that has a 60 angle of curvature, the curvature radius was 5 mm, whereas the inner diameter of the canal was 1.5 mm. All the files were rotated in artificial canals until they fracture. The resistance to cyclic fatigue was determined by counting the number of cycles to frac

... Show More
Scopus (1)
Scopus