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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 Sep 30 2022
Journal Name
Iraqi Journal Of Science
Investigation of Ground Density Distributions and Charge Form Factors for 14,16,18,20,22N using Cosh Potential
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     The bound radial wave functions of Cosh potential which are the solutions to the radial part of Schrodinger equation are solved numerically and used to compute the size radii; i.e., the root-mean square proton, neutron, charge and matter radii, ground density distributions and elastic electron scattering charge form factors for nitrogen isotopes 14,16,18,20,22N. The parameters of such potential for the isotopes under study have been opted so as to regenerate the experimental last single nucleon binding energies on Fermi's level and available experimental size radii as well.

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Publication Date
Tue Mar 14 2023
Journal Name
Iraqi Journal Of Science
Thermodynamic and kinetic Calculation for the Binding of Nickel (II) with Some Chelating Agents
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Chelating agents were used in a chelation therapy to detoxify heavy metals and toxins and convert them to an inactive form which was excreted out of the body. Nickel is one of these toxic heavy metal when presented in a high values over its allowable limit. This work studies the complexation of some amino acid (Glycine, Histidine, and Arginine) with nickel (II) ion and compare the result with complexation of EDTA (the synthesized amino acid) used in the chelation therapy. Our experiment were performed in a phosphate buffer of PH (7.2) and in a different temperature (283, 288,293, 298, 303)K . The results show a high tendency for these amino acid to nickel ion with an equilibrium constant in arrange of [KNi(II)-EDTA(17.2×108) > KNi(II

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Publication Date
Thu Mar 30 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Determination of Cefalexin by Direct (UV- Vis) Spectrophotometer and Indirect(Flame Atomic Absorption) Technique
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         A new method for the determination of the drug cefalexin in some Pharmaceuticals using (UV-Vis) and  indirect Flame Atomic Absorption Spectrophotometer (FAAS) , Fe III should forms a chelating complex with cefalexin (CEX –Fe III) at pH (1-8) and the best pH for the formation of (CEX –Fe III) chelating complex was (2) .The complex extracted with Methanol  and  Dimethy-Sulphoxide .The mole-ratio method has been used to determine the structure of chelate (CEX - Fe III) and found to be 2:1 LM ( Ligand : Metal.) .

Keywords : Cefalexin , chelating complex.

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Study the Effect of Ceramic Coating on the Performance and Emissions of Diesel Engine
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In this study, the effect of ceramic coating on the performance and gases emission on diesel engine was investigated. A four-stroke, direct injected, single cylinder, diesel engine was tested at constant speed and at different load conditions without coating. Then, the inlet and exhaust valves faces were coated by about 500µm with ceramic materials. Ceramic layers were made of YttriaStabilized Zirconia (YSZ), and NiCrAl as a bond coat. The coating technique adapted in this work is the flame spray method. The engine with valves ceramiccoated research was tested for the same operation conditions of the engine (without coating). The results indicate a reduction in both fuel consumption by about 7.6% and particulate emissions by about (13

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Publication Date
Tue Mar 30 2021
Journal Name
Iraqi Journal Of Science
Relationship Between Orexin-A and Insulin Resistance in Patients with Type 2 Diabetes Mellitus
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Background: Orexin-A is an orexigenic hormone that plays an important role in the metabolism of blood glucose, insulin, and insulin resistance (IR). The pathogenesis of type 2 diabetes mellitus (T2DM) is related to the abnormality in insulin and IR. However, no sufficient studies to date have clearly shown the association of orexin-A with biochemical parameters related to T2DM.

Objectives: The aim of this study was to determine the relation of orexin-A with IR and how they associate with physiological changes in T2DM patients. Understanding this relation will offer some pharmacological tools to reduce some complications in diabetes.

Materials and Methods: A total of 41 T2

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Publication Date
Sat Apr 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Risks That Facing Tourism And The Managing Methods In The contemporary Challenges Theoretical study
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Tourist business organizations face a challenging and the risks dynamic environment reflected its impact on the community and generate extra under pressure in the responsibilities and burdens of exceptional and affected much of factors, accidents and risks as a result of the actions and attitudes of disasters variety may exceed the geography of States border, which requires the absorption of risks facing the tourism and how to manage and deal with them scientific and reasonable grounds for the diagnosis and treatment of risk and how to reduce the aggravation and the different kinds.

As risks affecting the most important and vital to organizations as a tourist aspects of the market share and styles tourist

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Publication Date
Sun Mar 01 2009
Journal Name
Baghdad Science Journal
A Study of structural and electrical properties ofCuIn (Sex Te1-x) 2 thin films
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structural and electrical of CuIn (Sex Te1-x)2

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Publication Date
Thu Apr 27 2023
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Prevalence and Demographic characteristics of Metabolic Syndrome in Iraqi Patients with Acute Coronary Syndrome
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Background: The demographic characteristics of Iraqi patients with the metabolic syndrome (MS) and presenting with acute coronary syndrome (ACS) has been scarcely studied before.

Aim of the study To study the socio-demographic characteristics of a group of Iraqi patients with MS presenting with ACS.

Patients and Methods: A convenience sample of 150 cases presenting with ACS and admitted to the coronary care unit (CCU) of Al-Yarmouk Teaching Hospital in Baghdad from mid-January through July 2011 were included in the current cross-sectional study. The data needed for the study was collected through a direct interview to fill a questionnaire by all cases carried out by a consu

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Publication Date
Thu Jun 25 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Diuretic Effect of Prosopis farcta in Comparison with Spironolactone and Hydrochlorothiazide in Hypertensive Rats
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Prosopis farcta has been used traditionally for several diseases as cardiovascular, kidney, diabetes, bacterial infection and it has diuretic activity. This study was designed to evaluate the diuretic effects of P. farcta extract in comparison with spironolactone and hydrochlorothiazide in normal and hypertensive rats.Forty eight rats, were divided into Two groups. The First group was consist of Twelve normotensive rats, to represent the control group and normal treated group receiving 50 mg/Kg of P. farcta extract; Six rats in each group.

The Second group involved 36 hypertensive rats, were divided into six subgroups, each of six rats. The First subgroups served as a positive control, the Second, Third

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Publication Date
Tue Mar 28 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Design, Synthesis, Characterization and Comparative Cytotoxic Evaluation of bis-(2- mercaptoacetate) gold (III) chloride
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In recent years , the interest in gold (III) species have gained more and more attention for cancer chemotherapy , this was stimulating by the possibility to develop new agents with mode of action and clinical profile different from the established platinum metalodrugs.

With this frame, recently new square planar Au(III)  complexes (Au(L)(L')n); where L=SCH2COO- ; L'=HSCH2COO- had been synthesized with S/O – donor ligands.

In this article and by the aim to replace, one of (L') ligand by anion chloride ligand (which supposedly more relevant for the biodistribution of the compound than for its pharmacodynamic effects), new complex (Au(L')

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