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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 Jun 30 2011
Journal Name
Al-khwarizmi Engineering Journal
Extraction of Zn (II) and Cu (II) Ions Using PEG (300) - KCl Salt Aqueous Two-Phase Systems
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In this paper the process of metal ions extraction (Zn(II) and Cu(II)) was studied in PEG-KCl aqueous two phase system was investigated without using an extracting agent. The experimental runs were performance at constant temperature (25 oC), constant mixing time (30 min), and constant PH of the solution (about 3). The effect of KCl salt concentration (from 10% to 25%), volumetric phase ratio of PEG solution to KCl solution (from 0.5 to 2), and the initial metal ion concentration (from 0.25 ml to 2 ml of 1 gm/L solution) were investigated on the percent extraction of Zn(II) and Cu(II). The results indicated that the percent extraction of metal ions increase with increasing of salt concentration and phase ratio, and slightly de

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Publication Date
Sat Jul 08 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Estimation of Superoxide Dismutase, Matrix-metalloprotinase-9, and Interleukin -18 in Patients with Type Two Diabetes Mellitus
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Antioxidant status imbalance and inflammatory process are cooperative events involved in type 2 diabetes mellitus. This study aimed to investigate     superoxide dismutase as a potential biomarkers of antioxidant imbalance, matrix-metaloprotinase-9,   and interleukin -18  as biomarkers of inflammation in serum and to estimate  the effects of other confounding factors  gender, age and finally measuring the relation among the interested biomarkers.

This case - control study included 50 patients,   and   45 of  healthy subjects matched age –gender were also enrolled  in this study as a control group.    The   focused &nbsp

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
Dynamical Behavior of Two Predators-One Prey Ecological System with Refuge and Beddington –De Angelis Functional Response
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     The dynamical behavior of an ecological system of  two predators-one prey updated with incorporating prey refuge and Beddington –De Angelis functional response had been studied in this work, The essential mathematical features of the present model have been studied  thoroughly. The system has local and global stability when certain conditions are met.  had been  proved respectively.  Further, the system has no saddle node bifurcation but transcritical bifurcation and Pitchfork bifurcation are satisfied while the Hopf bifurcation does not occur. Numerical illustrations are performed  to validate the model's applicability under consideration. Finally, the results are included in the form of points in agreement with the obt

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Publication Date
Wed Feb 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
(The trade-off between privatization Options General contracting firms Using the strategic analysis of the external environment
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Discussed the research variables are important, privatization options and strategic analysis of the external environment, and that the purpose of the research is the trade-off between privatization options and choose the most appropriate alternative in proportion to the external environment, the research aims to determine the privatization the most appropriate option for companies and public contracting, showing the importance of the study provide the privatization of public companies as a strategy can all its way public sector organizations from the transfer of work practices or private sector organizations and mechanisms to it as contributing to improving the level of skills Develop the current and future level of performance,

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Publication Date
Fri Jan 15 2010
Journal Name
Joijrnal Of College Ofeducation
Association between Insulin Resistance and Mellitus type 1 in children
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Aim of the study is to find any correlation between obesity (insulin resistance) and type I diabetes in children. Obesity and diabetes mellitus are the common health problems, and obesity is common cause of the insulin resistance. The results revealed marked increased in glucose, insulin, HbAlc and insulin resistance in obese diabetic type I patients comparing to control group they were obese and non-obese found to be within normal values for glucose, insulin, FIbAlc , and insulin resistance.

Publication Date
Thu Jul 21 2022
Journal Name
Neuro Quantology
Astronomical Observation between Diffraction Limited Coherent and Incoherent Imaging Systems
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Numerical simulations are carried out to evaluate the coherence concept’s effect on the performance regarding the optical system, when observing and imaging the planet’s surface. In numerous optical approaches, the coherence qualities of light sources play an important role. This paper provides an overview about the mathematical formulation of temporal and spatial coherence and incoherence properties of light sources. The circular aperture was used to describe the optical system like a telescope. The simulation results show that diffraction-limited for incoherent imaging system certainly improves the image. Yet, the quality of the image is degraded by the light source's highly spatial and temporal coherence properties, resulting in a

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Publication Date
Wed Sep 30 2020
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Performance Comparison between Recycled Single Stage and Double Stage Hydrocyclones
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   This research presents a comparison of performance between recycled single stage and double stage hydrocyclones in separating water from water/kerosene emulsion. The comparison included several factors such as: inlet flow rate (3,5,7,9, and 11 L/min), water feed concentration (5% and 15% by volume), and split ratio (0.1 and 0.9). The comparison extended to include the recycle operation; once and twice recycles. The results showed that increasing flow rate as well as the split ratio enhancing the separation efficiency for the two modes of operation. On the contrary, reducing the feed concentration gave high efficiencies for the modes. The operation with two cycles was more efficient than one cycle. The maximum obtained effici

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Publication Date
Sat Jul 03 2021
Journal Name
Periodicals Of Engineering And Natural Sciences (pen)
Comparison between VG-levy and Kernel function estimation with application
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Publication Date
Wed Jun 14 2023
Journal Name
Al-academy
Classroom communication in art education lessons between concept and function
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The issue of communication and communication is receiving increasing attention in both contemporary studies and educational literature, and these studies emphasize the importance of studying communication within the classroom, which inevitably applies to the importance of relationships and tensions in the field of teaching art in particular because it is an emotional field that provides an opportunity for communication competencies and skills to be prominent and take Its wide scope, both among the students themselves and between teachers and students. The means of communication are the vessel in which the cultural relations and the commonalities between people revolve. The process of building relationships between students depends in man

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Publication Date
Thu May 05 2022
Journal Name
Alkindy College Medical Journal
Correlation between Body Mass Index and Nonalcoholic Fatty Liver Disease
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Background: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder globally. The prevalence is 25% worldwide, distributed widely in different populations and regions. The highest rates are reported for the Middle East (32%). Due to modern lifestyles and diet, there has been a persistent increase in the number of NAFLD patients. This increase occurred at the same time  where there were also increases in the number of people considered being obese all over the world. By analyzing fatty liver risk factors, studies found that body mass index, one of the most classical epidemiological indexes assessing obesity, was associated with the risk of fatty liver. Objectives: To assess age, sex, and body mass index (BMI) as

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