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Determination and evaluation of the orbital transition methods between two elliptical earth orbits
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To transfer a satellite or a spacecraft from a low parking orbit to a geosynchronous  orbit, one of the many transition methods is used. All these methods need to identify some orbital elements of the initial and final orbits as perigee and apogee distances. These methods compete to achieve the transition with minimal consumption of energy, transfer time and mass ratio consumed ), as well as highest accuracy of transition. The ten methods of transition used in this project required designing programs to perform the calculations and comparisons among them.

     The results showed that the evaluation must depend on the initial conditions of the initial orbit and the satellite mechanical exception as well as the target orbit. The most efficient methods of transition in terms of energy required were, sequentially, methods 10, 1, 8, 9, and 2, whereas the least efficient in terms of energy consumption, fuel and  transition time were, sequentially, methods 5,6, and 7. Method 3 was the most efficient when the orbit needed to change the inclination with the transition. The first phase of multi-stage transition is the most energy consuming.

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Publication Date
Mon May 15 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Finite Difference Method for Two-Dimensional Fractional Partial Differential Equation with parameter
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 In this paper, we introduce and discuss an algorithm for the numerical solution of two- dimensional fractional partial differential equation with parameter. The algorithm for the numerical solution of this equation is based on implicit and an explicit difference method. Finally, numerical example is provided to illustrate that the numerical method for solving this equation is an effective solution method.

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Publication Date
Thu Apr 01 2021
Journal Name
Basra Journal Of Science
Organic Field Effect Transistor Based on P3HT with Two Different Gate Dielectrics
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The electrical performance of bottom-gate/top source-drain contact for p-channel organic field-effect transistors (OFETs) using poly(3-hexylthiophene) (P3HT) as an active semiconductor layer with two different gate dielectric materials, Polyvinylpyrrolidone (PVP) and Hafnium oxide (HfO2), is investigated in this work. The output and transfer characteristics were studied for HfO2, PVP and HfO2/PVP as organic gate insulator layer. Both characteristics show a high drain current at the gate dielectric HfO2/PVP equal to -0.0031A and -0.0015A for output and transfer characteristics respectively, this can be attributed to the increasing of the dielectric capacitance. Transcondactance characteristics also studied for the three organic mater

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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Compare between result of analysis of variance after and before use analysis covariance to Split-blocks design
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This research aims to study the important of the effect of analysis of covariance manner for one of important of design for multifactor experiments, which called split-blocks experiments design (SBED) to deal the problem of extended measurements for a covariate variable or independent variable (X) with data of response variable or dependent variable Y in agricultural experiments that contribute to mislead the result when analyze data of Y only. Although analysis of covariance with discussed in experiments with common deign, but it is not found information that it is discussed with split-Blocks experiments design (SBED) to get rid of the impact a covariance variable. As part application actual field experiment conducted, begun at

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Publication Date
Sun Dec 03 2017
Journal Name
Iosr Journal Of Pharmacy And Biological Sciences
Relationship between Lipid Peroxidation and Integrity of Sperm Plasma Membrane in a Sample of Iraqi Infertile Men
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The current study aims to investigate the relationship between lipid peroxidation, represented by seminal malondialdehyde (MDA) level, and integrity of sperm plasma membrane, represented by the hypo-osmotic swelling (HOS) test score, in infertile men. One hundred and twenty Iraqi men (20 fertile and 100 infertile) shared in this study during their attendance to the High Institute for Infertility Diagnosis and Assisted Reproductive Technologies/Al- Nahrain University. The mean age of the fertile men was (30.46±0.78) years while the mean age of infertile men was (32.58±0.64) years with the duration of infertility (5.36±0.33) years. Semen samples were collected and the parameters of seminal fluid analysis were assessed; also, the HOS

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Publication Date
Fri Jan 01 2021
Journal Name
Indian Journal Of Forensic Medicine & Toxicology
Evaluation of Morphological (Macroscopic and Microscopic) Parameters of Placentas in Pregnancies Complicated by Preeclampsia, Diabetes and Preeclampsia and Diabetes.
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This study was done to compare the morphometric parameters of placentas in well controlled patients with preeclampsia, diabetes, and preeclampsia-diabetes with that of normal uncomplicated placentas. Patients & Methods: A total of Twenty four placentas were freshly collected. Six placentas for control group and eighteen placentas for complicated group (preeclamptic-diabetic and preeclamptic--diabetic subgroups). The placentas were grossly examined (shape, number of cotyledons, weight, and thickness). After suitable fixation, tissue processing and sectioning, the sections were stained by hematoxylin and eosin to study the general morphology and morphometry of the following parameters: number of terminal villi, number of syncytial knots, numb

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Publication Date
Sat Jun 15 2019
Journal Name
Journal Of Baghdad College Of Dentistry
The accuracy of cone-beam computed tomography in the evaluation of boney support of teeth among patients with a unilateral cleft of lip and palate among IraqiPopulation
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Background: To evaluate the bony supports of the teeth adjacent to the area of cleft in patient with unilateral cleft lip and palate and to compare these measurements with the measurements of the same teeth in non-cleft side by using CBCT. Materials and methods: The CBCT scans of 30 patients having cleft lip( unilateral) and palate(unilateral), were analyzed and the measurements of the alveolar bony support for teeth that are adjacent to the cleft area were measured with those teeth located on opposite side (non- clef) side. For each tooth, the measurements will taken for the distance between the( cementoenamel junction) (CEJ) and the bony crest (AC) at the( buccal area) was measured and the thickness of the buccal plate At zero, one, tw

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Publication Date
Sun Dec 29 2019
Journal Name
Iraqi Journal Of Science
Evaluation of the Hydrochemical Characteristics of Groundwater and its Suitability for Desalination to Product Potable Water in Tolul Al-Baj, Salahaldin, Iraq
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The study area, Tlul Al-Baj, suffers from a shortage of fresh water and most people depend on groundwater for different uses (drinking, domestic, irrigation, etc.).

The present research aims to select the most suitable wells for desalination and production of potable water in Tlul Al-Baj area.

Twenty-two samples of groundwater were collected to evaluate the hydrochemical properties of groundwater in the shallow aquifer in the area and to determine their suitability for desalination purposes. The study included measuring the physicochemical characteristics of groundwater, such as total hardness (TH), total dissolved solids(TDS), sodium adsorption ratio (SAR), sodium ratio (Na%), turbidity (Tur), pH…etc. Chemical anal

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Publication Date
Wed Aug 31 2022
Journal Name
Iraqi Journal Of Science
Correlation between Tumor Necrosis Factor–Alfa and Anti-tyrosine Phosphatase with Obesity and Diabetes Type 2
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     This study was done to find a correlation between adipokines such as tumor necrosis- alpha (TNF-α)  and autoantigens such as anti-tyrosine phosphatase (IA2) with obesity and type 2 diabetes mellitus (T2DM). For this purpose, one hundred forty adult males were selected. 90 of them were diagnosed with type 2 diabetes and 50 healthy males). The subjects were divided into four groups. Group 1 had healthy controls with body mass index (BMI) between 18.5-25, group 2 had individuals who suffered from obesity only (BMI above 30), group 3 consisted of diabetes patients and group 4 had individuals who were diagnosed with both obesity and diabetes. The enzyme immunoassay was intended for quantification determination of TNF in serum. The

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Publication Date
Sun May 30 2021
Journal Name
Iraqi Journal Of Science
Prevalence Rate and Correlation Between Triglyceride Level and Human Body Mass Index in Sulaimani Province, Iraq
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The condition of elevated concentrations of triglyceride in the blood is called hypertriglyceridemia, which triggers the onset of some physiological disorder. This study was carried out to find the correlation between body weight and hypertriglyceridemia. Out of 518 cases, 342 individuals were underweight, with body mass index (BMI) values of ≤18, while their mean serum triglyceride level was 172.4 ± 25.2mg/dl. In addition, 99 cases had normal BMI of >18, whereas 60 were overweight (BMI = 25-29), with mean serum triglyceride level of 182.3 ± 15.9. Also, 17 cases were obese (BMI >30), where the mean triglycerid

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Publication Date
Wed May 10 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Genetic Relationship Between Heavy Metals Resistance and β- Lactamase Production In E. Coli and Staphylococcus Aureus
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  This study is a trail to know if the genes controlling some of heavy metals resistance ( lead, zinc, cadmium, cromium) in two types of pathogenic bacteria  E. coli  as gram negative bacteria and S. aureus as gram positive bacteria, present on the β-lactamase plasmid.     Ten isolates of each bacterial types which produced β-lactamase enzyme, were cultivated in the presence of acridine orange. The growing in the presence of acridine orange resulted in loss of the β-lactamase genes in S. aureus and E. coli, and loss of the heavy metals resistance in S. aureus, while the resistance of E. coli against heavy metals still without any change.   The results indicate that the genes for heavy

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