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A N-Radon Based OFDM Trasceivers Design and Performance Simulation Over Different Channel Models
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In this paper a new method is proposed to perform the N-Radon orthogonal frequency division multiplexing (OFDM), which are equivalent to 4-quadrature amplitude modulation (QAM), 16-QAM, 64-QAM, 256-QAM, ... etc. in spectral efficiency. This non conventional method is proposed in order to reduce the constellation energy and increase spectral efficiency. The proposed method gives a significant improvement in Bit Error Rate performance, and keeps bandwidth efficiency and spectrum shape as good as conventional Fast Fourier Transform based OFDM. The new structure was tested and compared with conventional OFDM for Additive White Gaussian Noise, flat, and multi-path selective fading channels. Simulation tests were generated for different channels parameters values including multi-path gains vector, multi-path delay time vector, and maximum Doppler shift. © 2009 Springer Science+Business Media, LLC.

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Publication Date
Sun Aug 13 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Construction of Complete (k,n)-arcs in the Projective Plane PG(2,11) Over Galois Field GF(11), 3 ï‚£ n ï‚£ 11
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        The purpose of this work is to construct complete (k,n)-arcs in the projective 2-space PG(2,q) over Galois field GF(11) by adding some points of index zero to complete (k,n–1)arcs 3 ï‚£ n ï‚£ 11.         A (k,n)-arcs is a set of k points no n + 1 of which are collinear.         A (k,n)-arcs is complete if it is not contained in a (k + 1,n)-arc

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Publication Date
Sun Apr 30 2023
Journal Name
Iraqi Journal Of Science
Simulation of Fraunhofer Diffraction for Plane Waves using Different Apertures
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In this paper a two dimensional numerical simulation have been applied using
MATLAB program for generating Fraunhofer diffraction pattern from different
apertures. This pattern is applied for three types of apertures, including, circular,
square, and rectangular functions, and it's could be generated any wavelength in the
visible light. The studying demonstrated the capability and the efficiency of optical
imaging systems to observe a point source at very long distance. The circular
aperture shows better results across the shape of Fraunhofer pattern and optical
transfer function (otf). Also, the minimum values of the normalized irradiance of
different diffracted apertures have been computed at different dimension

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Publication Date
Mon Apr 01 2024
Journal Name
Journal Of Environmental Chemical Engineering
A critical review describes wastewater photocatalytic detoxification over Bi5O7I-based heterojunction photocatalysts: Characterizations, mechanism insight, and DFT calculations
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Publication Date
Wed Feb 27 2019
Journal Name
Iraqi Journal Of Science
UV-VIS Absorption Spectral Studies of N, N′-Bis(salicylidene)ethylenediamine (Salen) in Different Solvents
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In the present study, the influence of various solvents on UV-VIS absorption spectra of N,N-Bis(salicylidene)ethylenediamine (Salen) has been investigated. Salen ligand has two absorption maxima (around 260 and 320 nm). To explain the obtained spectra, the frequencies and molar absorptivity values were combined with solvent properties using a total solvatochromic equation suggested by the Kamlet and Taft. The multiparametric examination denotes that non-specific dipolar interactions of the solvents (π*) with the solute play a significant role in absorption maxima in pure solvents. The ionization constant (pKa) of salen in methanol has been determined by spectrophotometric measurements. Two graphical methods have been applied

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Publication Date
Sun Sep 05 2010
Journal Name
Baghdad Science Journal
Design and Testing a Neutrons and Gamma-Rays Multilayer Shield Using Different Groups of Cross – Sections
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A preventing shield for neutrons and gamma rays was designed using alternate layers of water and iron with pre-fixed dimensions in order to study the possibility of attenuating both neutrons and gamma-rays. ANISN CODE was prepared and adapted for the shield calculation using radiation doses calculation: Two groups of cross-section were used for each of neutrons and gamma-rays that rely on the one – dimensional transport equation using discrete ordinate's method, and through transforming cross-section values to values that are independent on the number of groups. The memory size required for the applied code was reduced and the results obtained were in agreement with those of standard acceptable document samples of cross –section, this a

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Publication Date
Sun Mar 05 2017
Journal Name
Baghdad Science Journal
Cache Coherence Protocol Design and Simulation Using IES (Invalid Exclusive read/write Shared) State
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To improve the efficiency of a processor in recent multiprocessor systems to deal with data, cache memories are used to access data instead of main memory which reduces the latency of delay time. In such systems, when installing different caches in different processors in shared memory architecture, the difficulties appear when there is a need to maintain consistency between the cache memories of different processors. So, cache coherency protocol is very important in such kinds of system. MSI, MESI, MOSI, MOESI, etc. are the famous protocols to solve cache coherency problem. We have proposed in this research integrating two states of MESI's cache coherence protocol which are Exclusive and Modified, which responds to a request from reading

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Publication Date
Sun Jun 05 2011
Journal Name
Baghdad Science Journal
A Study of Some Physical Properties for Binary System of Cyclohexane with n-decane and 1-pentanol at Different Temperatures
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mixtures of cyclohexane + n-decane and cyclohexane + 1-pentanol have been measured at 298.15, 308.15, 318.15, and 328.15 K over the whole mole fraction range. From these results, excess molar volumes, VE , have been calculated and fitted to the Flory equations. The VE values are negative and positive over the whole mole fraction range and at all temperatures. The excess refractive indices nE and excess viscosities ?E have been calculated from experimental refractive indices and viscosity measurements at different temperature and fitted to the mixing rules equations and Heric – Coursey equation respectively to predict theoretical refractive indices, we found good agreement between them for binary mixtures in this study. The variation of th

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Publication Date
Sat Mar 31 2018
Journal Name
Journal Of Engineering
Energy and Exergy Analysis of Dual Channel Solar Air Collector with Different Absorber Plates Geometry
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Flat-plate collector considers most common types of collectors, for ease of manufacturing and low price compared with other collectors. The main aim of the present work is to increase the efficiency of the collector, which can be achieved by improving the heat transfer and minimize heat loss experimentally. Five types of solar air collectors have been tested, which conventional channel with a smooth absorber plate (model I), dual channel with a smooth absorber plate (model II), dual channel with perforating “V” corrugated absorber plate (model III), dual channel with internal attached wire mesh (model Ⅳ), and dual channel with absorber sheet of transparent honeycomb, (model Ⅴ). The dual channel collector used for

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Publication Date
Thu Feb 15 2018
Journal Name
Ijca
Experimental Investigation and Performance Simulation of Kit Horizontal Axis Wind Turbine
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Publication Date
Sun Jan 16 2022
Journal Name
Iraqi Journal Of Science
Performance Evaluation of IPv6 Header Compression over MPLS via Satellite
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Broadband satellite is playing a main role in provision global coverage and onboard processing ability over IP networks to assess user applications. In order to lower the cost, get better security, solve IPv4 addressing limitation, expand the expected advantages of modern routing and mobility characteristics; the next-generation satellite systems ought to support IPv6 and seamlessly incorporate with terrestrial networks including wireless local loops. Satellite communication links have a number of limitations compared to terrestrial communications networks such as large delay and high header overhead for IPv6 consumes the bandwidth and causes lower transmission effectiveness; however, the quality of service (QoS) (such as delay, jitter,

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