Preferred Language
Articles
/
alkej-611
Peak to Average Power Ratio Reduction of OFDM Signals Using Clipping and Iterative Processing Methods
...Show More Authors

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Nov 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Analysis of the relationship between the prices of wheat and rice importer in Iraq and crude oil prices and the exchange rate using the ARDL model
...Show More Authors

Since the beginning of 21st century, the prices of Agricultural crops have increased. This Increases is accompanied with that increases of crude oil prices and fluctuation of a dollar exchange rate as a dominant currency used in the global trade. The paper aimed to analysis the short run and long run cointegration relationships between prices of some of Agricultural crops imported by Iraq such as wheat and rice crops and both the crude oil prices and the Iraq dinar exchange rate a gained America dollar using ARDL model. The results show the long run equilibrium between they three variable throng the error correction mechanizem. The results also show the significant and economically sound effects of cru

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Feb 01 2006
Journal Name
Political Sciences Journal
عرض كتاب المدخل الى دراسة الاستراتيجية
...Show More Authors

عرض كتاب المدخل الى دراسة الاستراتيجية

View Publication Preview PDF
Crossref
Publication Date
Sun Jun 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Comparing Bayesian methods to estimate the failure probability for electronic systems in case the life time data are not available
...Show More Authors

In this research, we find the Bayesian formulas and the estimation of Bayesian expectation for product system of Atlas Company.  The units of the system have been examined by helping the technical staff at the company and by providing a real data the company which manufacturer the system.  This real data include the failed units for each drawn sample, which represents the total number of the manufacturer units by the company system.  We calculate the range for each estimator by using the Maximum Likelihood estimator.  We obtain that the expectation-Bayesian estimation is better than the Bayesian estimator of the different partially samples which were drawn from the product system after  it checked by the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jun 20 2023
Journal Name
Baghdad Science Journal
Enhancement of corrosion protection of metal carbon steel C45 and stainless steel 316 by using inhibitor (Schiff base) in sea water
...Show More Authors

This research has presented a solution to the problem faced by alloys: the corrosion problem, by reducing corrosion and enhancing protection by using an inhibitor (Schiff base). The inhibitor (Schiff base) was synthesized by reacting of the substrates materials (4-dimethylaminobenzaldehyde and 4-aminoantipyrine). It was diagnosed by infrared technology IR, where the IR spectrum and through the visible beams proved that the Schiff base was well formed and with high purity. The corrosion behavior of carbon steel and stainless steel in a saline medium (artificial seawater 3.5%NaCl) before and after using the inhibitor at four temperatures: 20, 30, 40, and 50 C° was studied by using three electrodes potentiostat. The corrosion behavior was

... Show More
View Publication Preview PDF
Scopus (18)
Crossref (6)
Scopus Crossref
Publication Date
Fri Aug 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Types of the Fiber Glass-Mat on Fatigue Characteristic of Composite Materials at Constant Fiber Volume Fraction: Experimental Determination
...Show More Authors

The aim of this work is to study the influence of the type of fiber glass –mat on fatigue behavior of composite material which is manufactured from polyester and E-glass (woven roving, chopped strand mat (CSM)) as a laminate with a constant fiber volume fraction (VF) of 33%. The results showed that the laminates reinforced with E-glass (woven roving) [0/90, ±45.0/90] and [0/90, CSM, 0/90] have lower fatigue strength than the laminates reinforced with E-glass [0/90]3,[CSM]3 and [CSM, 0/90, CSM]  although they had different tensile strength; the best laminate was [0/90]3 .

View Publication Preview PDF
Publication Date
Fri Jun 20 1930
Journal Name
College Of Islamic Sciences
Achieving the book of reaction to the end of   Book of alimony from the manuscript of the Forum of the Evangelist Sheikh Ibrahim bin Mohammed bin Ibrahim Halabi (P. 956 e
...Show More Authors

Achieving the Book of Return to the End of the Book of Alimony from the Manuscript of the Forum of the Abhar of the Sheikh (Abraham Bin
Muhammad ibn Ibrahim al-Halabi (d. 956 AH), who was a member of the Hanafi sect, was a long man
Fiqh, interpretation, modernity, Arab sciences, and readings
Hanafi as well as that he was Abid Zahid and the reason for his claim to this book that asked him some
He asked him to take advantage of it
Al-Hanafiya said, mentioning the sources from which he was taken, and presented his opinion and evidence on the correct
He mentioned the issues of the Hanafi jurisprudence in his book according to the chapters of the jurisprudence
Reaction is done to what you have achieved previously in the h

... Show More
View Publication Preview PDF
Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Thermo Elasto-Plastic Analysis of Rotating Axisymmetrical Bodies Using Modified Von-Mises Yield Criterion
...Show More Authors

In the present work, the behavior of thick-walled cylinder of elasto-plastic material (polymeric material) has been studied analytically. The study is based on modified Von-Mises yield criterion (for non metallic material). The equations of stress distribution are obtained for the cylinder under general cases of elastic expansion, plastic initiation and elastic-plastic expansion.

        A computer program is developed for evaluating the stress distribution. The solution is carried out for worst boundary conditions when the cylinder is subjected to the combination of pressure load, inertia load, and temperature gradient.

        The results are presente

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Removal of Suspended Solids Using Pumice Stone in Integrated Fixed Film Activated Sludge Process
...Show More Authors

Wastewater treatment plants operators prefer to make adjustments because they are more cost effective, to use the existing tank instead of building new ones. In this case an imported materials would be  used as bio-loads to increase biomass and thus maintain efficiency as the next organic loading increases.In the present study, a local substance "pumice stone" was used as a biological carrier in the aeration tank, and the experiments were carried out in five stages: without biological carriers, filling ratio of 4%,10%,20%, and25% with pumice stone, the maximum organic loading at each stage (1.1884, 1.2144, 1.9432, 2.7768, 3.3141)g BOD /l.d respectively.Other experiments were carried out to determine the best filling ratio, the SS remova

... Show More
View Publication Preview PDF
Scopus (4)
Scopus Clarivate Crossref
Publication Date
Wed Nov 28 2018
Journal Name
International Journal Of Engineering & Technology
Improvement of Gypsum Soil by Using Polyurethane to Reduce Erosion and Solubility of Irrigation Canals
...Show More Authors

The reducing of erosion and the solubility of irrigation canals soils which constructed on gypsum soil is important in civil and water resources engineering. The main problem of gypsum soils is the presence of gypsum which represents one of most complex engineering problems, especially when accompanied by the moving of water which represent dynamic load along the canal. There are several solutions to this problem, in this research “Poly urethane” is used to give the gypsum soil sufficient hardness to reduce the solubility and erosion, after compacting the soil in the canal, percentages of Poly urethane was used to making cover to the soil by mixing percent of soil with Poly urethane, and the ratio was as follows: (5 and 10) % an

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Wed Mar 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
The Extent of the Practice of Iraqi Banks to Manage Profits Using the (LLp it) Model and Its Reflection on the Tax Base, A Case Study of A Sample of Iraqi Private Banks Listed in The Iraqi Stock Exchange
...Show More Authors

The research aims to identify the extent to which Iraqi private banks practice profit management motivated by reducing the taxable base by increasing the provision for loan losses by relying on the LLP it model, which consists of a main independent variable (net profit before tax) and independent sub-variables (bank size, total debts to total equity, loans granted to total obligations) under the name of the variables governing the banking business. (Colmgrove-Smirnov) was used to test the normal distribution of data for all banks during the period 2017-2020, and then find the correlation between the main independent variable sub and the dependent variable by means of the correlation coefficient person, and then using the multiple

... Show More
View Publication Preview PDF
Crossref