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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
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
The Effect of Heat Treatment on the Magnetic and Mechanical properties offe - Ni alloys.
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The aim of this work is studying the binary system ??'??? Ni?)with two ratios (y=36,80) by using casting method for preparing the samples.Magnetic and Mechanical properties have been studidt different httrea^nttem^rature.All the alloys were found a ferromagnetic behavior and sensitive to the heat treatment. Best properties were found at the heat treatment 1100 C°.A significant different results were found above 1100C° for lower magnetic and mechanical values. This is possibly due to the change on the degree of magnetic moment orders, in which most of the moments are started to remove from coupled ferromagnetically.?

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Publication Date
Fri Jan 26 2024
Journal Name
Iraqi Journal Of Science
Studying of Frequencies, Normal Modes of Vibration and Electronic Charge Densities of 5Radialene molecule
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PM3 and DFT (6-311G/ B3LYP) level calculations were carried out for the 5Radialene molecule, which is exhibit D5h symmetry. The obtained equilibrium geometry was applied for the calculation of all 3N−6 vibration frequencies, and for the analysis of its normal coordinates and symmetry species, in addition to some physical properties such as heat of formation, total energy, dipole moment and energy difference of HOMO and LUMO levels (ΔELUMO-HOMO), using Gaussian-03 program. The so calculated frequencies according to DFT (6-311G/ B3LYP) fall in the ranges;
CH2 str. (3016-3098 cm-1), C=C str. (1662-1709cm-1), ring (C-C str.) (1268-1464 cm-1). δCH2 (890-1317cm-1), (δCCC) (562-631cm-1), γCH2 (738-946cm-1) and γring (γCCC) (

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Publication Date
Wed Jan 01 2020
Journal Name
Journal Of Clinical And Experimental Dentistry
The effect of osseodensification on implant stability and bone density: A prospective observational study
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Background: The aims of this study were to evaluate the effect of implant site preparation in low-density bone using osseodensification method in terms of implant stability changes during the osseous healing period and peri-implant bone density using CBCT. Material and methods: This prospective observational clinical study included 24 patients who received 46 dental implants that were installed in low-density bone using the osseodensification method. CBCT was used to measure the bone density pre- and postoperatively and implant stability was measured using Periotest® immediately after implant insertion and then after 6 weeks and 12 weeks postoperatively. The data were analyzed using paired t-test and the probability value <0.05 was conside

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Publication Date
Sun Jan 30 2022
Journal Name
Iraqi Journal Of Science
Haematological and Demographic Study in Children Infected with Enterobiasis in Al Diwaniyah Province, Iraq
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     Enterobius vermicularis infection is considered as one of the important causes of anaemia and malnutrition among children. This topic has recently received an increased amount of attention.  The objective of this study is to evaluate the demographical, anthropometrical, nutritional, and  haematological status of E. vermicularis infection among children. This study was conducted in Al Diwaniyah province, south of Iraq, for the period of October 2020 to the end of January 2021. The study included 122 children from both genders (males, n= 61, and females, n=61) and their ages ranged between 1 and 14 years. Nutritional status, body mass index (BMI), BMI percentile, and wei

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Publication Date
Tue Apr 01 2014
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Comparative Study of Allopurinol and Uralyt-4 in patients with Hyperuricemia in Diyala Governorate.
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Background: Hyperuricemia represents a major public health problem; approximately most population has hyperuricemia, serum uric acid ≥6.5 mg/dL in women and ≥7.0 mg/dL in men.
Allopurinol has been approved for the treatment of hyperuricemia patients. Epidemiological and experimental studies suggest a linkage between hyperuricemia and type of treatment.
Objective: To assess the effect of allopurinol and uralyt- 4 and mixture of two drugs (allopurinol and uralyt-4) in hyperuricemia patients
Methods: A total of 60 serum patients with history of hyperuricemia, obtained from Baladrus Hospital in Diyala governorate, were included in this study. In addition, ten normal uric acid level persons used as contro

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Publication Date
Thu Jul 01 2021
Journal Name
Iraqi Journal Of Science
Alterations of Obestatin, Cardiac Markers and Lipid Profile Levels in Type 2 Diabetes Mellitus
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The current investigation aimed to test the alterations of the levels of obestatin hormone, lipid profile and cardiac function markers in relation to hyperglycemia in patients with non-insulin diabetes mellitus. The study included 118 diabetic subjects (56 males, 62 females) and 60 healthy non-diabetic subjects (30 males, 30 females). Diabetic and healthy subjects were age-matched. Serum levels of obestatin, lipid profile markers including total cholesterol (STC), triglycerides (STG), low and high density lipoproteins (LDL-C and HDL-C), as well as cardiac function markers including, creatine kinase and lactate dehydrogenase enzymes were determined in all subjects. The findings revealed a remarkable decrease in the level of serum obestati

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Publication Date
Wed Jul 17 2019
Journal Name
Iraqi Journal Of Science
Evaluation of the Aquifer Properties Between Al-Khassa Dam and Kirkuk Structure - NE Iraq
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This paper aims to evaluate the hydraulic characteristics of the aquifer between Al-khassa dam and Kirkuk structure, Kirkuk/ NE Iraq. Pumping tests applied for selected wells in the area to evaluate the hydraulic characteristics of the aquifer, special distribution of the water table and groundwater movement direction of the groundwater, the hydraulic properties results of five single pumping test in the study area showed that the transmissivity (T) is ranged between (2.01 to 7. 5 m2/day ), storage coefficient (Sc) ranged (6.4 * 10-3 to 7.3 * 10-2) and the hydraulic conductivity (K) is ranged between (0.025 to 0.35 m/day) that calculated by Winlog software, groundwater discharge of the area is equal to

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Publication Date
Sun Feb 03 2019
Journal Name
Iraqi Journal Of Physics
Impact of thickness and heat treatment on some physical properties of thin Cu2SnS3 films
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Copper tin sulfide (Cu2SnS3) thin films have been grown on glass
substrate with different thicknesses (500, 750 and 1000) nm by flash
thermal evaporation method after prepare its alloy from their
elements with high purity. The as-deposited films were annealed at
473 K for 1h. Compositional analysis was done using Energy
dispersive spectroscopy (EDS). The microstructure of CTS powder
examined by SEM and found that the large crystal grains are shown
clearly in images. XRD investigation revealed that the alloy was
polycrystalline nature and has cubic structure with preferred
orientation along (111) plane, while as deposited films of different
thickness have amorphous structure and converted to polycrystalline

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Publication Date
Wed Feb 08 2023
Journal Name
Iraqi Journal Of Science
Pathogenicity of Carbapenems and Third Generation Cephalosporins Resistant K. pneumoniae in Murine Urinary System
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One hundred and nine clinical lactose fermenter isolates were collected from different samples (urine, stool, wound swab, blood, and sputum) , in a period from February 2014 till May 2014. All samples gathered from Alyarmok laboratories, Alkadimiya laboratories, and Baghdad teaching laboratories which are situated at Baghdad city. Fifty three (48,62%) isolates were identified as Klebsiella pneumoniae depending on microscopic characterization , conventional biochemical tests and then the identification confirmed with API 20E system . The rest of 56(51, 38%) isolates represented other bacteria.Susceptibility test was achieved to all fifty-three K. pneumoniae isolates using five antibiotic disks (Ceftazidime, Ceftriaxone, Cefotaxime, Imipen

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Publication Date
Fri Nov 09 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Evaluation of Anemia among Lactating Mothers and their Children Under Two Years of Age
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Objective: The aim of this study is to evaluate anemia among lactating women and their children less than 2 years of
age.
Methodology: The study was done on (148) lactating mothers and their children under 2 years of age in the primary
health care center at AL-Salam Quarter/Baghdad from l/10/2009 to 15/10/2010.
Result: This study recommends that there is a significant relationship between anemic mothers and their children. The
study also revealed that there is (77.8%) from nursing mothers in the age groups (25-29) who suffered from anemia,
while (23.1%) for the age group (20-24) did not have anemia
Recommendation: We encourage the use of breast milk or iron-fortified infant formula only for any milk-based part
of

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