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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
Thu Dec 15 2022
Journal Name
Al-academy
The controversy of aesthetic interpretation between the sculptures and their titles Contemporary Iraqi Sculpture "Experiments in Contemporary Iraqi Sculpture Exhibition as a Model"
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The research tagged with the controversy of aesthetic interpretation between the sculptures and their titles in contemporary Iraqi sculpture, “Exhibition of Experiments in Contemporary Iraqi Sculpture as a Model”, and it is one of the new research that contributes to strengthening the critical path in the Iraqi fine movement, as the first chapter dealt with the research problem stemming from the question: What is the impact of the aesthetic hermeneutic controversy between the title and the title in contemporary Iraqi sculpture?, and do the titles of the sculptural works help to understand or enhance their contents?, The research objective included: To identify the controversy of the aesthetic interpretation of sculptures and their ti

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Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Cognitive Bias and Organizational Inertia are Two Functions of Strategic Change An Experimental Study in Amman Stock Market
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The research aims at considering the reality of cognitive bias and organizational inertia as determinants of strategic change in a sample of companies listed in Amman Stock Market. To achieve objectives of the research, a model consisting of two independent variables has been designed, namely:

(1) The cognitive bias resulting from (escalating commitment, analogy, previous assumptions, representative generalization, command and control, convergent thinking), and (2) Organizational inertia due to (Icarus discrepancy, power distribution, rooted organizational culture), and a dependent variable, strategic change in (leadership patterns, strategy, the organization per se). 

From the model two main hypotheses were derived;

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Publication Date
Sat Oct 01 2011
Journal Name
Iraqi Journal Of Physics
Two dimensional grating and efficiency enhancement of Si photovoltaic cells by surface texturing using UV femtosecond laser pulses
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A fast laser texturing technique has been utilized to produce micro/nano surface textures in Silicon by means of UV femtosecond laser. We have prepared good absorber surface for photovoltaic cells. The textured Silicon surface absorbs the incident light greater than the non-textured surface. The results show a photovoltaic current increase about 21.3% for photovoltaic cell with two-dimensional pattern as compared to the same cell without texturing.

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Publication Date
Tue Jan 01 2019
Journal Name
Molecular Biology Research Communications
Association study of two single nucleotide polymorphisms rs10757278 and rs1333049 with atherosclerosis, a case-control study from Iraq
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Publication Date
Wed Mar 01 2017
Journal Name
Journal Of Al-nahrain University-science
Cytological Effects of Mutagenic Agents and NaCl on Mitotic Division in Two Iraqi Rice (Oryza sativa L.) Genotypes
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This study was carried out to determine the effects of NaCl (0.00, 50, 100, 150, 180 or 200) mM and two different types of mutagens chemical mutagen ethyl methyl sulphonate (EMS) at 0.5% and physical mutagen UV-B irradiation (40 min time exposure), on mitotic division in two Iraqi rice genotypes Amber 33 (A33) and Amber Baghdad (AB). Different concentrations of NaCl were used. Mitotic index (MI %) was decreased significantly by increasing NaCl concentration, however the highest mitotic index was recorded in mutated genotypes with EMS and UV-B. Different abnormal chromosomes were noticed in mutated plants. Results showed high percentage of abnormal chromosomes in EMS mutated genotypes. In addition no significant differences between genotypes

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Publication Date
Mon Jun 05 2023
Journal Name
Al-khwarizmi Engineering Journal
Extraction of Bovine Serum Albumin by Aqueous Two-Phase System Using PEG4000/Sodium Citrate and PEG8000/Sodium Phosphate
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Aqueous Two Phase System (ATPS) or liquid-liquid extraction is used in biotechnology to recover valuable compounds from raw sources. In Aqueous Two-Phase Systems, many factors influence the Partition coefficient, K, (which is the ratio of protein concentration in the top phase to that in the bottom phase) and the Recovery percentage (Rec%). In this research, two systems of ATPS were used: first, polyethylene glycol (PEG) 4000/Sodium citrate (SC), and the second, PEG8000/ Sodium phosphate (SPH), for the extraction of Bovine Serum Albumin (BSA). The behavior of Rec% and K of pure (BSA) in ATPS has been investigated throughout the study by the effects of five parameters: temperature, concentration of polyethylene glycol (P

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Publication Date
Sat Jan 01 2022
Journal Name
Journal Of Clinical And Experimental Dentistry
Cusp deflection and fracture strength of root canal filled premolars with two access cavities designs (Conservative vs Traditional)
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Publication Date
Fri Aug 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Types of the Fiber Glass-Mat on Fatigue Characteristic of Composite Materials at Constant Fiber Volume Fraction: Experimental Determination
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The aim of this work is to study the influence of the type of fiber glass –mat on fatigue behavior of composite material which is manufactured from polyester and E-glass (woven roving, chopped strand mat (CSM)) as a laminate with a constant fiber volume fraction (VF) of 33%. The results showed that the laminates reinforced with E-glass (woven roving) [0/90, ±45.0/90] and [0/90, CSM, 0/90] have lower fatigue strength than the laminates reinforced with E-glass [0/90]3,[CSM]3 and [CSM, 0/90, CSM]  although they had different tensile strength; the best laminate was [0/90]3 .

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Publication Date
Mon Apr 01 2019
Journal Name
Plant Archives
Association between BTN1A1 gene polymorphism and some reproductive efficiency indicator and heat toleranceinholsteincows
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This study was conducted in Al-Salam station for Dairy cattle/private sector, for the period from 1-11-2016 to 1-11-2017, to determine the association between BTN1A1 gene polymorphism and reproductive efficiency indicator and heat tolerance in 50 Holstein cows. The results of BTN1A1 gene analysis showed a highly significant Different (P<0.01) between genotypes of BTN1A1 gene’s genotypes AA, AB the percentage were 72.00, 28.00 % respectively. Results showed that services per conception and days open was significantly (P<0.05) affected by polymorphism of BTN1A1 gene and for cows with AA genotype, there was also a significant difference (P<0.05) between the genotypes of BTN1A1 gene for IgG concentration in calves blood who belong to mother

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Publication Date
Thu Dec 29 2016
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Comparison in Some Biochemical and Hematological Tests Between Chronic Hepatitis B and C
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  Chronic viral hepatitis is an important health problem in the world, where hepatitis B virus (HBV) or hepatitis C virus (HCV) infections are the main causes of liver insufficiency. The study included 100 blood samples from patients with chronic viral hepatitis, fifty of them with HBV infection and 50 with HCV infection. Twenty apparently healthy age and gender matched subjects were included as a control group. Out of the 50 patients with HBV, 36(72%) were males and 14(28%) were females. Thirty two (64%) patients with HCV were males and 18(36%) were females. The mean age for HBV patients was 36.9 ± 15.8 year and for HCV patients it was 39.9 ±14.2 year.  The results of the liver function tests showed no significant differ

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