Preferred Language
Articles
/
joe-2542
PAPR Reduction of OFDM Signals Using Clipping and Coding
...Show More Authors

The problem of the high peak to average ratio (PAPR) in OFDM signals is investigated with a brief presentation of the various methods used to reduce the PAPR with special attention to the clipping method. An alternative approach of clipping is presented, where the clipping is performed right after the IFFT stage unlike the conventional clipping that is performed in the power amplifier stage, which causes undesirable out of signal band spectral growth. In the proposed method, there is clipping of samples not clipping of wave, therefore, the spectral distortion is avoided. Coding is required to correct the errors introduced by the clipping and the overall system is tested for two types of modulations, the QPSK as a constant amplitude modulation and 16QAM as a varying amplitude modulation.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Apr 12 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
the Optical Properties of Electrostatic Design and Study Mirror By using Bimurzaev Technique
...Show More Authors

In this research a computational simulation  has been carried out on the design and properties of the electrostatic mirror and a mathematical expression has been suggested  to represent the axial potential of an electrostatic mirror. The electron beam path using the Bimurzaev  technique had been investigated as mirror trajectory with the aid of Runge – Kutta  method. The spherical and chromatic aberration coefficients of mirror has computed and normalized in terms of the focal length. The choice of the mirror depends on the operational requirements. The Electrode shape of mirror two electrodes has been determined by using package SIMION computer program. Computations have shown that the suggested potentials giv

... Show More
View Publication Preview PDF
Publication Date
Sat Oct 29 2022
Journal Name
Current Trends In Geotechnical Engineering And Construction
Simulation Design and Performance of a Residential Complex Using Liquefied Petroleum Gas Network
...Show More Authors

The population has been trying to use clean energy instead of combustion. The choice was to use liquefied petroleum gas (LPG) for domestic use, especially for cooking due to its advantages as a light gas, a lower cost, and clean energy. Residential complexes are supplied with liquefied petroleum gas for each housing unit, transported by pipes from LPG tanks to the equipment. This research aims to simulate the design and performance design of the LPG system in the building that is applied to a residential complex in Baghdad taken as a study case with eight buildings. The building has 11 floors, and each floor has four apartments. The design in this study has been done in two parts, part one is the design of an LPG system for one building, an

... Show More
View Publication
Scopus Crossref
Publication Date
Fri Mar 01 2019
Journal Name
Iraqi Journal Of Physics
Synthesis and structural characteristics of Co1-xCuxFe2O4 magnetic ferrite nanoparticles using hydrothermal technique
...Show More Authors

In this work, copper substituted cobalt ferrite nanoparticles with
chemical formula Co1-xCuxFe2O4 (x=0, 0.3, and 0.7), has been
synthesized via hydrothermal preparation method. The structure of
the prepared materials was characterized by X-ray diffraction (XRD).
The (XRD) patterns showed single phase spinel ferrite structure.
Average crystallite size (D), lattice constant (a), and crystal density
(dx) have been calculated from the most intense peak (311).
Comparative standardization also performed using smaller average
particle size (D) on the XRD patterns of as-prepared ferrite samples
in order to select most convenient hydrothermal synthesis conditions
to get ferrite materials with smallest average particl

... Show More
View Publication Preview PDF
Crossref (6)
Crossref
Publication Date
Mon Apr 01 2019
Journal Name
Materials Chemistry And Physics
Investigation of silica polymorphs stratified in siliceous geode using FTIR and XRD methods
...Show More Authors

View Publication
Crossref (54)
Crossref
Publication Date
Mon Mar 01 2021
Journal Name
Journal Of Physics: Conference Series
Green synthesis of gold NPs by using dragon fruit: Toxicity and wound healing
...Show More Authors
Abstract<p>In this work, the study of <italic>Hylocereus undatus</italic> properties was done by studying quantitative phytochemical compounds and seeking for total phenolic compounds, synthesis of gold nanoparticles was created via reduction of aqueous gold ions with the aqueous fruit extract of The <italic>Hylocereus undatus</italic> (dragon). The synthesized AuNPs were asserted by using (Uv-Vis) spectrophotometer; Fourier transforms infrared (FI-IR) spectroscopy, Atomic force microscope (AFM), Scanning Electron Microscopy (SEM) Zitasizer. The absorbance for SPR is noticed in 546 nm by using Uv-Visible spectroscopy The SEM and AFM analysis evidenced the particle size betwee</p> ... Show More
View Publication
Scopus (25)
Crossref (20)
Scopus Crossref
Publication Date
Tue Dec 13 2022
Journal Name
Lecture Notes In Networks And Systems
Design and FPGA Implementation of Matrix Multiplier Using DEMUX-RCA-Based Vedic Multiplier
...Show More Authors

View Publication
Scopus (1)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Using of concepts "conservatism & accrual" and their reflection in enhancing of quality of financial reporting
...Show More Authors

The use of Conservatism  significant impacts on the financial statements and thus on financial reporting which is produced by these lists so Rate Some of the professionals that the principle of accounting while Rate of others as a constraint, and brought this category based on the uses of this restriction sometimes used the accountant this restriction and especially with the uncertainties in the Sometimes it may collide with some of the cases in which the accountant may be forced to leave in custody as a result of emergence of economic events that gave rise to rights or future commitments should be disclosed.

The emergence in custody mainly was due to the uncertainty and its essence is to report on a

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jul 01 2015
Journal Name
Journal Of Engineering
Enhancing the Performance of Piezoelectric Energy Harvesters Using Permanent Magnets
...Show More Authors

A cantilevered piezoelectric beam with a tip mass at its free end is a common energy harvester configuration. This paper introduces a new principle of designing such a harvester which increases the generated voltage without changing the natural frequency of the harvester: The attraction force between two permanent magnets is used to add stiffness to the system. This magnetic stiffening counters the effect of the tip mass on the natural frequency. Three setups incorporating piezoelectric bimorph cantilevers of the same type in different mechanical configurations are compared theoretically and experimentally to investigate the feasibility of this principle. Theoretical and experimental results show that magnetically stiffe

... Show More
View Publication Preview PDF
Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Chaotic behaviour of the Rossler model and its analysis by using bifurcations of limit cycles and chaotic attractors
...Show More Authors

The behaviour of certain dynamical nonlinear systems are described in term as chaos, i.e., systems' variables change with the time, displaying very sensitivity to initial conditions of chaotic dynamics. In this paper, we study archetype systems of ordinary differential equations in two-dimensional phase spaces of the Rössler model. A system displays continuous time chaos and is explained by three coupled nonlinear differential equations. We study its characteristics and determine the control parameters that lead to different behavior of the system output, periodic, quasi-periodic and chaos. The time series, attractor, Fast Fourier Transformation and bifurcation diagram for different values have been described.

View Publication
Scopus (37)
Crossref (25)
Scopus Clarivate Crossref
Publication Date
Sun Jun 30 2013
Journal Name
Al-khwarizmi Engineering Journal
Thermodynamic and Kinetic Study of the Adsorption of Pb (II) from Aqueous Solution Using Bentonite and Activated Carbon
...Show More Authors

The adsorption of Pb(II) ions onto bentonite and activated carbon was investigated. The effects of pH, initial adsorbent dosage, contact time and temperature were studied in batch experiments. The maximum adsorption capacities for bentonite and activated carbon were 0.0364 and 0.015 mg/mg, respectively. Thermodynamic parameters such as Gibbs free energy change, Enthalpy change and Entropy change have been calculated. These thermodynamic parameters indicated that the adsorption process was thermodynamically spontaneous under natural conditions and the adsorption was endothermic in nature. Experimental data were also tested in terms of adsorption kinetics, the results showed that the adsorption processes followed well pseudo second- order

... Show More
View Publication Preview PDF