Preferred Language
Articles
/
QBamBYcBVTCNdQwC6S_k
A Partial CSI Estimation Approach for Downlink FDD massive-MIMO System with Different Base Transceiver Station Topologies
...Show More Authors

Massive multiple-input multiple-output (massive-MIMO) is a promising technology for next generation wireless communications systems due to its capability to increase the data rate and meet the enormous ongoing data traffic explosion. However, in non-reciprocal channels, such as those encountered in frequency division duplex (FDD) systems, channel state information (CSI) estimation using downlink (DL) training sequence is to date very challenging issue, especially when the channel exhibits a shorter coherence time. In particular, the availability of sufficiently accurate CSI at the base transceiver station (BTS) allows an efficient precoding design in the DL transmission to be achieved, and thus, reliable communication systems can be obtained. In order to achieve the aforementioned objectives, this paper presents a feasible DL training sequence design based on a partial CSI estimation approach for an FDD massive-MIMO system with a shorter coherence time. To this end, a threshold-based approach is proposed for a suitable DL pilot selection by exploring the statistical information of the channel covariance matrix. The mean square error of the proposed design is derived, and the achievable sum rate and bit-error-rate for maximum ratio transmitter and regularized zero forcing precoding is investigated over different BTS topologies with uniform linear array and uniform rectangular array. The results show that a feasible performance in the DL FDD massive-MIMO systems can be achieved even when a large number of antenna elements are deployed by the BTS and a shorter coherence time is considered.

Scopus Clarivate Crossref
View Publication
Publication Date
Wed Jun 22 2022
Journal Name
Journal Of Medicinal And Chemical Sciences
Organo-Clay Composites of Intercalated 4-Methylaniline and Its Schiff Base Derivative: Preparation and Characterization
...Show More Authors

4-methylaniline and its Schiff base derivative were intercalated into the Bentonite clay interlayers in a solid state reaction followed by a condensation reaction to produce two organo-clay composites. X-ray diffraction was used to identify the changes in basal spacing of montmorillonite layers which exhibited noticeable alteration before and after the formation of the composites. FT-IR spectra, on the other hand, were utilized for identifying the structural compositions of the prepared materials as well as the formation of the intercalated Schiff base derivative. The surface morphology of the composites was examined by Scanning Electron Microscopy SEM and Atomic Force Microscope AFM, which reflected some differences in the surface of prepa

... Show More
Publication Date
Wed Sep 12 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis Characterization and Analytical Applications of New Chelating Resin of Formaldehyde-condensed Phenolic Schiff base.
...Show More Authors

  A new chelating phenolic Schiff base containing phthalate imide pendant group resin was synthesized by three steps. The first step includes synthesis of 2-(4-aminobiphenyl-4-ylcarbamoyl) benzoic acid (1), Via reaction of pthalic anhydride with benzidine. In the second lines, the compound that we obtained in the first step was reacted with o-hydroxybenzaldehyde to obtain phenolic Schiff base 2-(4'-(2-hydroxybenzylideneamino) bephenyl-4-yl carbamoyl) benzoic acid (2) The third step includes prepared resin during intensification Schiff base derived with formaldehyde inan alkaline middle. Thepthale amice acid, Schiff base and resin were characterized by various instrumental techniques like FT-IR, 1HNMR ,13CNMR an

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Feb 26 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of certain chemical surface treatments on repair bond strength of some denture base materials
...Show More Authors

Background: Fracture of different types of acrylic denture base is a common problem associated with dental prosthesis. Studies suggested that the repair strength may be improved by several means including surface treatment with chemical agents. The aim of the study was to evaluate the effect of surface treatment with acrybond-bonding agent and monomer on fractured denture base in respect to transverse, tensile and shear bond strength and evaluation of the mode of failure by light microscope. Materials and methods: Two hundred seventy specimens were prepared and divided into 3 groups according to the material used (regular conventional, rapid simplified and high impact) heat cure acrylic. The specimen in each groups were prepared specificall

... Show More
View Publication Preview PDF
Publication Date
Thu Jun 30 2022
Journal Name
International Journal Of Drug Delivery Technology
Synthesis of New Substituted Coumarin Derivatives containing Schiff-Base as Potential Antimicrobial and Antioxidant Agents
...Show More Authors

By unusual method for separating two isomers of a substituted nitro-coumarin using a soxhlet extractor and in controlling temperature to get a selective nitration reaction, several new Schiff base coumarins were synthesized from nitro coumarins as starting material, which were reduced by Fe in glacial acetic acid to produce corresponding amino coumarin derivatives. Then the latter was reacted with different aromatic aldehydes to produce the desired Schiff bases derivatives. After characterization by Fourier transform infrared (FT-IR), Proton nuclear magnetic resonance (1HNMR) and Carbon-13 nuclear magnetic resonance (C-NMR), all these compounds were evaluated as potential Antimicrobial and Antioxidant Agents.

View Publication
Scopus (4)
Crossref (2)
Scopus Crossref
Publication Date
Mon Nov 15 2021
Journal Name
Aip Conference Proceedings
Oil skimming followed by coagulation/flocculation processes for oilfield produced water treatment and zero liquid discharge system application
...Show More Authors

The study focused on the treatment of real oilfield produced water from the East Baghdad field affiliated to the Midland Oil Company (Iraq) using an oil skimming process followed by a coagulation/flocculation process for zero liquid discharge system applications. Belt type oil skimmer was utilized for evaluating the process efficiency with various operating conditions such as temperature (17-40 °C) and time (0.5-2.5 hr.). Polyaluminum chloride (PAC) coagulant and polyacrylamide (PAM) flocculant was used to investigate the performance of the coagulation/flocculation process with PAC dosage (5-90 ppm) and pH (5-10) as operating conditions. In the skimming process, the oil content, COD, turbidity, and TSS decreased with an increase in tempera

... Show More
View Publication
Publication Date
Tue Dec 05 2023
Journal Name
Baghdad Science Journal
An improved neurogenetic model for recognition of 3D kinetic data of human extracted from the Vicon Robot system
...Show More Authors

These days, it is crucial to discern between different types of human behavior, and artificial intelligence techniques play a big part in that.  The characteristics of the feedforward artificial neural network (FANN) algorithm and the genetic algorithm have been combined to create an important working mechanism that aids in this field. The proposed system can be used for essential tasks in life, such as analysis, automation, control, recognition, and other tasks. Crossover and mutation are the two primary mechanisms used by the genetic algorithm in the proposed system to replace the back propagation process in ANN. While the feedforward artificial neural network technique is focused on input processing, this should be based on the proce

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Using system dynamics model and the statistical indicators for Road Map of "Green government departments" project In Iraq
...Show More Authors

Abstract                                                         

The issue of the protection of the environment is a shared responsibility between several destinations and sectors, and constitutes a main subject in which they can achieve sustainable development. In the sectors of government programs can be set up towards the establishment of the government sector to the green environment, so to be the implementati

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Sep 01 2020
Journal Name
Journal Of Engineering
An Adaptive Digital Neural Network-Like-PID Control Law Design for Fuel Cell System Based on FPGA Technique
...Show More Authors

This paper proposes an on-line adaptive digital Proportional Integral Derivative (PID) control algorithm based on Field Programmable Gate Array (FPGA) for Proton Exchange Membrane Fuel Cell (PEMFC) Model. This research aims to design and implement Neural Network like a digital PID using FPGA in order to generate the best value of the hydrogen partial pressure action (PH2) to control the stack terminal output voltage of the (PEMFC) model during a variable load current applied. The on-line Particle Swarm Optimization (PSO) algorithm is used for finding and tuning the optimal value of the digital PID-NN controller (kp, ki, and kd) parameters that improve the dynamic behavior of the closed-loop digital control fue

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Dec 07 2008
Journal Name
Baghdad Science Journal
Evaluation of home-mode ELISA system for thedetection of antibodies against Escherichia coli O157:H7 using purified lipopolysaccharide
...Show More Authors

An enzyme linked immunosorbent assay (ELISA) for the detection and quantitation of human immunoglobulin G (IgG) antibodies against vero- cytotoxine (VT) producing Escherichia coli serogroup O157:H7 was produced. E. coli O157: H7 lipopolysaccharide was extracted from locally isolated strains by using hot phenol- water method, followed by partial purification using gel filtration chromatography by sepharose- 4B. The purity of the lipopolysaccharide was checked by measuring the protein and nucleic acid content and then used as antigen. Four isolates of vero- cytotoxin producing E. coli serogroup O157:H7 was obtained by culturing 350 stool samples from children suffering from bloody diarrhea. These isolates were identified on bacteriological, s

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Jul 31 2021
Journal Name
Iraqi Journal Of Science
Stability Analysis and Assortment of Exact Traveling Wave Solutions for the (2+1)-Dimensional Boiti-Leon-Pempinelli System
...Show More Authors

     In this research, the Boiti–Leon–Pempinelli (BLP) system was used to understand the physical meaning of exact and solitary traveling wave solutions. To establish modern exact results, considered. In addition, the results obtained were compared with those obtained by using other existing methods, such as the standard hyperbolic tanh function method, and the stability analysis for the results was discussed.

View Publication Preview PDF
Scopus (5)
Scopus Crossref