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Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
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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.

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Publication Date
Fri Jan 08 2010
Journal Name
Al-kindy College Medical Journal
Maternal and fetal outcomes in emergency versus elective two or more previous cesarean deliveries
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Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Pharmaceutical Sciences And Research
Synthesis and biological activity of new esters derived from D-fructose-containing isoxazole moiety
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Background: Isoxazoles are an important class of five-membered unsaturated heterocyclic compounds. They show several applications in diverse areas such as pharmaceuticals, agrochemistry and industry. Isoxazoles are also found in natural sources showing insecticidal, plant growth regulation and pigment functions. Current study was conducted for synthesis of twenty five new Isoxazole derivatives and to evaluate the in vitro antibacterial activities of these derivatives. Methods: Benzaldoxime and their substituted [I] ae were prepared via addition-elimination reactions between aromatic aldehyde and hydroxylamine hydrochloride. In a second step, para-or meta-substituted benzaldoximes [I] ae were reacted with N-chlorosucceinimide in DMF to yield

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Publication Date
Fri Mar 25 2016
Journal Name
Oriental Journal Of Chemistry
Synthesis and Antioxidant Ability of New 5-amino-1,2,4-Triazole Derivatives Containing 2,6-dimethoxyphenol
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4-amino-3-(4-(((4-hydroxy-3,5dimethoxybenzyl)oxy)methyl)phenyl)-1,2,4-triazole-5-thione was synthesized by to method the first one from melt reaction of 4-(((4-hydroxy-3,5-dimethoxybenzyl)oxy)methyl)benzoic acid with Thiocarbonyldihydrazide, the second method from convert the corresponded acid hydrazide to potassium 2-(4-(((4-hydroxy-3,5-dimethoxybenzyl)oxy)methyl)benzoyl)hydrazinecarbodithioate salt then react with hydrazine hydrate. Newly Schiff base (7a-7f) were synthesized from reaction the 4-amino-1,2,4-triazol with substituted hydroxybenzaldehyde. The resulting compounds were characterized by IR, 1H-NMR, 13C-NMR, and HRMS data. 2,2-Diphenyl-1-picrylhydrazide (DPPH) and ferric reducing antioxidant power (FRAP) assays were used to scree

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Publication Date
Sun Jul 02 2023
Journal Name
Iraqi Journal Of Science
Synthesis, Characterization and Evaluation of Antimicrobial Activity for New Heterocyclic Derivatives Containing Pentagonal, HexagonalRings.
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This research, involved a series of some new compounds containing different hetero cyclic new pentagonal and hexagonal rings, through the reaction of 2-mercapto-3-phenyl-4(3H)quinazolinone (1) with chloroacetylchloride in the presence of potassium hydroxide, and dry dimethylformamide (DMF) as a solvent to obtain the intermediate compound (2). This compound is reacted with different reagents to give four routes, the first route include direct reaction with substituted-2-aminobenzothiazole under certain conditions to give new compounds (3-9). The second route involved condensation compound (2) with 5-substituted-2-amino-1,3,4-oxadiazole in the presence of potassium carbonate anhydrous to give new compounds (10-13).while the third route inv

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Publication Date
Fri Mar 30 2012
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Enhancement of Biogas production and organic reduction of sludge by different pre-treatment processes
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Anaerobic digestion (AD) is the most common process for dealing with primary and secondary wastewater sludge. In the present work, four pre-treatment methods (ultrasonic, chemical, thermal, and thermo-chemical) are investigated in Al-Rustumya Wastewater Treatment plant in order to find their effect on biogas production and volatile solid removal efficiency during anaerobic digestion.
Two frequencies of ultrasonic wave were used 30 KHz and 50 KHz during the pre-treatment. Sodium hydroxide was added in different amounts to give three pH values of 9, 10 and 11 in chemical pre-treating processes. The sludge was heated at 60oC and 80oC through thermal pre-treatment experiment. Also, the sludge was treated thermo-chemically at 80 oC and pH

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Publication Date
Mon Sep 01 2014
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Electronic payments system and its relationship to the effectiveness of commercial banks: Applied Research
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      That the electronic payments system plays an important role in the effectiveness of commercial banks by attracting domestic or foreign investors, especially in the banking sector , It must keep abreast of global developments and technology in the field of banking that lead to the effectiveness of the bank by providing modern banking services and good customer service that improves the reputation of the bank, as well as develop its activities and promotes economic development at the country level , The technological progress of the bank will increase the speed of conducting banking operations, accuracy and safer , here should be laws and regulations related to electronic payment systems keep pace with the la

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Publication Date
Thu Dec 29 2016
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Structural and Electrical Properties Dependence on annealing temperature of a-Ge:Sb/c-Si Heterojunction
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 In this work, we are Study the effect of annealing temperature on the structure of a-Ge films doped with Sb and the electrical properties of a-Ge:Sb/c-Si heterojunction fabricated by deposition of a-Ge:Sb film on c-Si by using thermal evaporation. Electrical properties of aGe:Sb/c-Si heterojunction include I-V characteristics in dark at different annealing temperatures and C-V characteristics and with the C-V characteristics suggest that the fabricated heterojunction was abrupt type, built in potential determined by extrapolation from 1/C2-V curve and show that the built - inpotential (Vbi) for the Ge:Sb/Si system increases with the increase of annealing temperatures

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Publication Date
Tue Dec 30 2008
Journal Name
Al-kindy College Medical Journal
Etiology of Bloody Diarrhea among Children Admitted to Maternity and Children ’ s Hospital-Erbil
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Background: Bloody diarrhea plays a major role in
morbidity and mortality especially in developing
countries, it is usually a sign of invasive enteric
infection, there is a thought that amoebic dysentery is
more common than bacillary dysentery in Iraq, and
from 1989 to 1997 amoebic dysentery increase from
20000to 550000 patients.
Objectives: This study aims to:
1. Outline the incidence of various infectious causes of
bloody diarrhea in Erbil district.
2. Assess the effect of multiple factors like age, sex,
source of water supply, etc... On the incidence of
amebic and bacillary dysentery.
3. To provide baseline data for making strategic plan to
reduce the diarrhoeal mortality and morbidity.
Met

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Publication Date
Fri Dec 08 2023
Journal Name
Iraqi Journal Of Science
AL-Dibdiba Formation Basin Hydrological Aspects Extraction Using GIS techniques and Quantitative Morphometric Analysis
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The drainage basin's hydrological aspect studying is considered to be important issue because of their influence (especially in arid to semi-arid regions) on the water management projects, agricultural management projects, and grazing ones. The importance of this study is coming from the fact that AL-Dibdiba formation basin climate is arid to semi-arid and there are human activities (habitation and agricultural) in the east part of it, so the water resources management is needed for this basin. The morphometric analysis illustrates the hydrological aspects in a quantitative form; the problem is the use of the traditional schemes in the calculation processes (such as the topographic map and the planmeter), which coast time and money and a

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Publication Date
Sun Oct 01 2006
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Childhood Idiopathic Thrombocytopenic Purpura: A Retrospective Analysis Of Clinical Features And Response To Treatment
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Background : A retrospective study was done in the Pediatric ward /AL-Kadhimiyia Teaching Hospital on cases diagnosed as idiopathic thrombocytopenic Purpura admitted since the first of January1992 – the end of December 2004.
Aim of the study : The objective of this paper is to review the natural history of idiopathic thrombocytopenic Purpura , presenting feature and response to treatment.
Patients and methods : The review included age ,sex , clinical presentation , physical finding , complications , investigation ,treatment and course of the diseases .
Results: total number of the patients were 65, peak age was between (2 -5) years, 40 cases (61.53%). Females were affected more than Males with male: female

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