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Peak to Average Power Ratio Reduction of OFDM Signals Using Clipping and Iterative Processing Methods
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One of the serious problems in any wireless communication system using multi carrier modulation technique like Orthogonal Frequency Division Multiplexing (OFDM) is its Peak to Average Power Ratio (PAPR).It limits the transmission power due to the limitation of dynamic range of Analog to Digital Converter and Digital to Analog Converter (ADC/DAC) and power amplifiers at the transmitter, which in turn sets the limit over maximum achievable rate.

        This issue is especially important for mobile terminals to sustain longer battery life time. Therefore reducing PAPR can be regarded as an important issue to realize efficient and affordable mobile communication services.

        This paper presents an efficient PAPR reduction method for OFDM signal. This method is based on clipping and iterative processing. Iterative processing is performed to limit PAPR in time domain but the subtraction process of the peak that over PAPR threshold with the original signal is done in frequency domain, not in time like usual clipping technique. The results of this method is capable of reducing the PAPR significantly with minimum bit error rate (BER) degradation.

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Publication Date
Tue Dec 11 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Impact of Adolescents' Family Meal Eating Patterns upon their Weight Control Behaviors at Secondary Schools in Baghdad City
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Objective: The study aimed to identify the adolescents' family meal eating patterns, and find out the relationship between adolescents' family meal eating patterns and their weight control behaviors. Methodology: A descriptive study was conducted on impact of adolescents' family meal eating patterns upon their weight control behaviors in secondary schools at Baghdad city, starting from 20th of April 2013 to the end of October 2014. Non- probability (purposive) sample of 1254 adolescents were chosen from secondary schools of both sides of Al-Karkh and Al-Russafa sectors. Data was collected through a specially

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Publication Date
Sat Sep 30 2023
Journal Name
Al–bahith Al–a'alami
Trends in Media Discourse during International Crises: An Analytical Study of the US Withdrawal from the Nuclear Deal
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The research focuses on the withdrawal of the United States from the nuclear agreement signed between the permanent members of the United Nations Security Council and the Islamic Republic of Iran concerning its nuclear program. This withdrawal has caused disruption in the official media discourse of the concerned countries. Therefore, the main question can be posed: Are there differences in the positions of countries related to the nuclear agreement, as well as those countries affected by it, before and after the official withdrawal of the United States on May 8, 2018?
The research aims to shed light on the trends in media discourse of the countries that signed the nuclear agreement and those affected by it b

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Crossref
Publication Date
Sun Dec 29 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
The static aging effect on the seedless synthesis of different ranges FAU-type zeolite Y at various factors
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This work investigates generating of pure phase Faujasite-type zeolite Y at the ranges chosen for this study via a static aging step in the absence of seeds synthesis. Nano-sized crystals may result when LUDOX AS-40 is used as a silica source for gel composition of range 6 and the crystallization step may be conducted for a period of 4 to 19 hr at 100 ⁰C. Moreover, large-crystals with high crystallinity pure phase Y zeolite can be obtained at hereinabove conditions but when hydrous sodium metasilicate is used as a silica source. The other selected ranges also offer pure phase Y zeolite at the same controlled conditions.

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Publication Date
Sat Apr 30 2022
Journal Name
Iraqi Journal Of Science
Fabrication of Vertical Axis Wind Turbine (VAWT) for a Water Pump at Low Speed Wind in Tikrit Region
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      We have designed, fabricated and studied the vertical axis wind turbine and its characterization. The system has been locally designed to pump water. It is considered as a one of the best options for low speed wind. The turbine has eight blades , each blade is 1.8m in length,  and the area dimension of the turbine 3.6 m2 . were investigated  the  best characterization of the system at low wind speed are Power turbine  depends on the wind speed. It was 280 Watt at 6m/s and 160 watt at 5m/s  , and  the power after the turbine decreasing to factor  1/3. The system torque was 20 N.m , Power coefficient cap  0.29 , Tip speed ratio 0.46. It is suitable to be used in Iraq region , and low cost for get the wat

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Publication Date
Tue Nov 13 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Approximation Solution of a Nonlinear Parabolic Boundary Value Problem Via Galerkin Finite Elements Method with Crank-Nicolson
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    This paper deals with finding the approximation solution of a nonlinear parabolic boundary value problem (NLPBVP) by using the Galekin finite element method (GFEM) in space and Crank Nicolson (CN) scheme in time, the problem then reduce to solve a Galerkin nonlinear algebraic system(GNLAS). The predictor and the corrector technique (PCT) is applied here to solve the GNLAS, by transforms it to a Galerkin linear algebraic system (GLAS). This GLAS is solved once using the Cholesky method (CHM) as it appear in the matlab package and once again using the Cholesky reduction order technique (CHROT) which we employ it here to save a massive time. The results, for CHROT are given by tables and figures and show

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Publication Date
Thu Jan 04 2024
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The role of organizational trust dimension in customer relationship management: Applied research in the general ethnic insurance company
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Abstract:

               The aim of the research is to verify the role of organizational trust as an “administrative” dimension of objective importance in the relationships adopted by the Iraqi General Insurance Company with customers, as it is one of the basic pillars in building and succeeding companies, which allows the provision of services with high confidence through the customer relationship management system in order to achieve The company's goal is to gain new customers, retain current customers, increase work in insurance companies, and develop the national economy by increasing the company's sales and profitability. The research

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Publication Date
Fri Dec 01 2017
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Humoral immune factor changes in group of patients with Non-muscle invasive bladder cancer treated with intravesical therapy.
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Publication Date
Wed Feb 01 2017
Journal Name
International Journal Of Science And Research (ijsr)
Performance Evaluation of the Organic Matter Removal Efficiency in Wastewater Treatment Plants; Case study Al- Diwaniyah WWTP in Iraq
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This study aims to assess the removal efficiency andestablish the BOD5 and COD statisticalcorrelation of the sewage flowing in Al-Diwaniyah wastewater treatment plant in Iraq during the study period (2005-2016). The strength of the influent wastewater entering the plant varied from medium to high in strength. High concentrations of BOD5 and COD in the effluent were obtained due to the poor performance of the plant. This was observed from the BOD5 /COD ratios that did not confirm with the typical ratios for the treated sewage. To improve the performance of this plant, regression equations for BOD5 and COD removal percentages were suggested which can be used to facilitate evaluation of liquid waste and optimal control process. The equations

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Publication Date
Thu Jan 01 2009
Journal Name
J. Of University Of Anbar For Pure Science
Estimation of the Normalized Difference Vegetation Index (NDVI) Variation for Selected Regions in Iraq for two Years 1990 & 2001
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The Normalized Difference Vegetation Index (NDVI) is commonly used as a measure of land surface greenness based on the assumption that NDVI value is positively proportional to the amount of green vegetation in an image pixel area. The Normalized Difference Vegetation Index data set of Landsat based on the remote sensing information is used to estimate the area of plant cover in region west of Baghdad during 1990-2001. The results show that in the period of 1990 and 2001 the plant area in region of Baghdad increased from (44760.25) hectare to (75410.67) hectare. The vegetation area increased during the period 1990-2001, and decreases the exposed area.

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Publication Date
Tue Mar 01 2022
Journal Name
Iraqi Journal Of Applied Physics
Fabrication of Solid Random Gain Media in Visible Region from Rhodamine Dye Solutions Containing Highly-Pure Titanium Dioxide Nanoparticles
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In this work, solid random gain media were fabricated from laser dye solutions containing nanoparticles as scattering centers. Two different rhodamine dyes (123 and 6G) were used to host the highly-pure titanium dioxide nanoparticles to form the random gain media. The spectroscopic characteristics (mainly fluorescence) of these media were determined and studied. These random gain media showed laser emission in the visible region of electromagnetic spectrum. Fluorescence characteristics can be controlled to few nanometers by adjusting the characteristics of the host and nanoparticles as well as the preparation conditions of the samples. Emission of narrow linewidth (3nm) and high intensity in the visible region (533-537nm) was obtained.

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