Preferred Language
Articles
/
alkej-132
Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
...Show More Authors

Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at high Doppler shifts with same SNR and target BER=10-4. It was shown that the performance at higher Doppler frequency shifts (<30Hz) was improved by more than 2dB over channel estimation at target BER=10-4 and 32QAM constellation used.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees21gr
Theoretical investigation of charge transfer at N3 sensitized molecule dye contact with TiO2 and ZnO semiconductor
...Show More Authors

We present a simple model of charge transfer current through sensitizer N3 molecule contact to TiO2 and ZnO semiconductors to calculate the charge transfer current. The model underlying depends on the fundamental parameters of the charge transfer reaction and it is based on the quantum transition theory approach. A transition energy, driving energy and potential barrier have been taken into account charge transfer current at N3 / TiO2 and N3 / ZnO devices with wide polarity solvents Acetic acid, 2-Methoxyethanol, 1-Butanol, Methyl alcohol, chloroform, N,N-Dimethylacetamide and Ethyl alcohol via the quantum donor-acceptor system.The effects of the transition energy and potential barrier are computed and discussion on charge transfer current.

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Aip Conference Proceedings
Theoretical calculation for sputtering yield of beryllium copper alloy bombarded by Argon, nitrogen and oxygen ions
...Show More Authors

View Publication
Scopus (3)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Wed Aug 09 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Relationship Between Lipid Peroxidation and Vitamine (E) ,  -Tocooherol Supplementation in Sera of Apparntly Healthy Individuals
...Show More Authors

  In an attempt to shed a light on the possible relationship between lipid peroxidation and some antioxidant.         The effect of vitamine E (as a potent antioxidant free radical scavenger) on the serum levels of Total cholesterol (TC) and Triacylglycerols (TG) was studied and the lipid peroxidation marker (MDA) was measured.       The study includes (50) healthy donors from males and females who had given vitamine E at a rate of (400IU) daily for one month and were divided into two groups. 1. Group (A) : included (25) males donors (20-40) years old, before and after giving vitamine E. 2. Group (B) : included (25) females donors (20-40) years old , before and af

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Preparation of some azo compounds by diazotization and coupling of 2- amino -5 – thiol -1,3,4- thiadizaole
...Show More Authors

2- amino -5- thiol-1,3,4- thiadiazole (S1) was prepared by cyclic locking of thiosemicarbazide in the presence of anhydrous sodium carbonate and CS2. diazotization of (S1) compound gave diazonium salt (S2) that reacts with different activated aromatic compounds to get the following azo compounds ,2 [(4- aminophenyl) diazenyl ] 1,3,4- thiazdiazole-5- thiol (S3) ,2-[4-amino- 1-naphthyl diazenyl] -1,3,4 – thiazdiazole-5-thiol (S4) , 3-amino-4-[(5- mercapto -1,3,4- thiadiazole -2-yl) diazenyl ] phenol(S5) ,1-[(5-mercapto-1,3,4-thiadiazole-2-yl) diazenyl] -2-naphthol (S6) , 5-{[4-(dimethylamino) phenyl] diazenyl}-1,3,4-thiadiazole-2- thiol(S7) ,5-{[4-(diethylamino) phenyl] diazenyl}-1,3,4- thiadiazole-2- thiol(S8) ,2- amino-5-[(5-mercapto-1,3

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Mar 15 2019
Journal Name
Al-khwarizmi Engineering Journal
Experimental and Theoretical Study of the Energy Flow of a Two Stages Four Generators Adsorption Chiller
...Show More Authors

This work is concerned with a two stages four beds adsorption chiller utilizing activated carbon-methanol adsorption pair that operates on six separated processes. The four beds that act as thermal compressors are powered by a low grade thermal energy in the form of hot water at a temperature range of 65 to 83 °C.  As well as, the water pumps and control cycle consume insignificant electrical power. This adsorption chiller consists of three water cycles. The first water cycle is the driven hot water cycle. The second cycle is the cold water cycle to cool the carbon, which adsorbs the methanol. Finally, the chilled water cycle that is used to overcome the building load. The theoretical results showed that average cycle cooling power

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Induction of chromosomal aberrations by zinc phosphide in of illiteracy sperm cells and eggs laboratory rats
...Show More Authors

1 - is not affected by illiteracy cells painful eggs after the first and seventh of the various concentrations used but found the effect of 21 and 35 days after treatment2 - repeat chromosomal aberrations illiteracy eggs cells no different distortions occurring sperm cells During Altnavra phase3 - increased chromosomal aberrations increase the dose especially for 21 and 35 days4 - The connective tissue is more sensitive phase of the pesticide from Altnavra phase

View Publication Preview PDF
Publication Date
Fri Jan 01 2021
Journal Name
Annals Of Parasitology
Association between genetic polymorphism of IL-27 (rs153109) and toxoplasmosis in Iraqi women with recurrent abortion
...Show More Authors

Scopus
Publication Date
Wed Jun 29 2022
Journal Name
College Of Islamic Sciences
The question of demand: definition, divisions, and examples from the controversy of the scholars of jurisprudence.
...Show More Authors

research summary

Praise be to Allah، and prayers and peace be upon His Messenger and His chosen one، his family، companions and his family and his family.

After that، this is a study on the question of the claim، as one of the controversial questions that are the mainstay of debates، and I looked at it: the limit of the question of the claim، its importance، its impact، its aspects of corruption، its sections، and the representation of its sections of the fundamentalist controversy;

The research was according to the following plan:

Introduction، in which she mentioned: the importance of the research topic and the reason for its selection، its questions، its l

... Show More
View Publication Preview PDF
Publication Date
Tue Oct 11 2022
Journal Name
College Of Islamic Sciences
The purposes of faith and its fruits in the light of the letters of light Prepare
...Show More Authors

What is meant by objectives: the purpose, secrets, judgment, and interests that the legislator set for each of its rulings is a doctrine and a law.

Faith is belief with certainty in God Almighty, and what is required of him in his divinity, lordship, names and attributes, belief in his angels, books, messengers, the Last Day and destiny, both good and bad.

And the purposes of faith are the wisdom and secrets contained in the Islamic faith and which achieve human well-being and happiness in the immediate and the future. And that the purposes of belief and faith are the essence of religion, rather it constitutes a basic pillar on which the basis of the intentional consideration as a whole, because the structure of worship i

... Show More
View Publication Preview PDF
Publication Date
Fri Aug 21 2009
Journal Name
Arab J Geosci
Mineralogical, geochemical, and geotechnical evaluation of Al-Sowera soil for the building brick industry in Iraq
...Show More Authors

The raw material soil of Al-Sowera factory quarry (quarry soil and mixture) used for building brick industry was tested mineralogically, geochemically and geotechnically. Mineral components of soil are characterized by Clay minerals (Palygoriskite and chlorite) and nonclay minerals like calcite, quratz, feldspar, gypsum and halite. The raw material is deficient in SiO2, Al2O3, K2O, Fe2O3 and MgO, while enriched in CaO. Loss on ignition and Na2O are in suitable level and appear to be concordant with the standard. Grain size analyses show that the decreasing sand and clay, and increasing silt ratio in both quarry soil and mixture caused decreasing in strength of brick during molding and after firing. The quarry soil is characterized by high p

... Show More