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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
Wed Mar 22 2017
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
COLLABORATIVE RELATIONSHIP BETWEEN CONSUMER RIGHTS IN THE ALGERIAN MARKET.: COLLABORATIVE RELATIONSHIP BETWEEN CONSUMER RIGHTS IN THE ALGERIAN MARKET.
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The current study aimed to identify key consumer rights and the nature of the work of organizations and traders in the Algerian market through the opinions of the study sample. To prove the hypotheses the researcher depended on the data obtained by the questionnaire prepared for this purpose. She distributed 384 questionnaires out of which only 300 were returned.
The data were analyzed using several statistical techniques such as the Statistical Package for Social Studies system, in addition to percentages, frequencies, and standard deviation.
And a number of conclusions and recommendations were presented. The most important results are:
- There is a strong correlation between safety and compensation rights.
- There is a st

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Publication Date
Sun Mar 01 2020
Journal Name
Periodicals Of Engineering And Natural Sciences
Employment of the genetic algorithm in some methods of estimating survival function with application
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Intended for getting good estimates with more accurate results, we must choose the appropriate method of estimation. Most of the equations in classical methods are linear equations and finding analytical solutions to such equations is very difficult. Some estimators are inefficient because of problems in solving these equations. In this paper, we will estimate the survival function of censored data by using one of the most important artificial intelligence algorithms that is called the genetic algorithm to get optimal estimates for parameters Weibull distribution with two parameters. This leads to optimal estimates of the survival function. The genetic algorithm is employed in the method of moment, the least squares method and the weighted

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Publication Date
Wed Dec 15 2021
Journal Name
Al-academy
Realism in the painting of Iraqi Kurdistan artists "A Study in methods of expression"
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The tagged research (realism in the Paintings of Iraqi Kurdistan artists, “a study of expression methods”) dealt with realism in an objective way, as well as the complexity of its concepts through its formations and formations. On realism and its historical dimension in concept and meaning, as for the second chapter, the research was focused on the methods of expression in painting, while the third chapter was concerned with the procedural applications of realistic methods of expression in the drawings of Iraqi Kurdistan, and according to these axes and to achieve the goal of the research, a number of Among the results are:
1- Realism documented the life of the Kurdish society in line with the developments of the era, as the sty

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Publication Date
Fri Jun 30 2023
Journal Name
Iraqi Journal Of Science
The Relation Between the Variation of Electrical Resistivity Values and Moisture of Soil at Baghdad University, Iraq
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     Six ERI profiles using Wenner Schlumberger array were carried out at Baghdad University (ALJadiriya campus) to investigate soil at two sites. The spacing between electrodes of four profiles surrounding the new building in the Campus at the first site is 1 m, and the profile length ranges from 50 to 90 m. In comparison, two across profiles in the garden to detect water seepage in the site. The inverted model of the studied profiles shows many high and low resistivity zone. The sedimentology and mineralogy of the soil samples analysis from a depth range of 15 to 100 cm from three pits confirm the high homogeneity of the soil in the studied site composed of (silt and clay). The low resistivity values coincided with the moisture a

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Publication Date
Thu Dec 15 2022
Journal Name
Al-academy
Strategies of brain-based learning theory and its impact on the achievement of students of the Department of Art Education in Teaching Methods
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The aim of the current research is to reveal the effect of using brain-based learning theory strategies on the achievement of Art Education students in the subject of Teaching Methods. The experimental design with two equal experimental and control groups was used. The experimental design with two independent and equal groups was used, and the total of the research sample was (60) male and female students, (30) male and female students represented the experimental group, and (30) male and female students represented the control group. The researcher prepared the research tool represented by the cognitive achievement test consisting of (20) questions, and it was characterized by honesty and reliability, and the experiment lasted (6) weeks

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Publication Date
Sat Dec 02 2017
Journal Name
Al-khwarizmi Engineering Journal
Biomechanical Aspects of Shoulder and Hip Articulations: A Comparison of Two Ball and Socket Joints
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The shoulder and hip joints though essentially both are ball and socket joints, show structural variability to serve functional needs.

This study aims at revealing some of the structural and functional properties of each of the two joints regarding the factors that contribute to the stability of any joint in the body, namely: bone, ligament, and muscle.

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Publication Date
Sat Mar 31 2018
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
A Comparison between the Product-Refill and the Equalization Oxygen Pressure Swing Adsorption Processes
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This work presents a design for a pressure swing adsorption process (PSA) to separate oxygen from air with approximately 95% purity, suitable for different numbers of columns and arrangements. The product refill PSA process was found to perform 33% better (weight of zeolite required or productivity) than the pressure equalization process. The design is based on the adsorption equilibrium of a binary mixture of O2 and N2 for two of the most commonly used adsorbents, 5A & 13X, and extension from a single column approach. Zeolite 13X was found to perform 6% better than zeolite 5A. The most effective variables were determined to be the adsorption step time and the operational pressure. Increasing the adsorption step

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Publication Date
Thu Nov 02 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Relationship Between the Attitude and Achievement in Mathematics for Intermediate Second Class Students
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Many studies mentioned that there is a decline in the a achievement of intermediate second class students in mathematics  . Parents and mathematics   teachers   had  emphasized   that  .  The  studies   related  this decline to the students weak attitude towards mathematics .

In spite  of the  importance  of this subject  , it has not been given enough attention  in research in our country . This research is an attempt to know  th e relationships  between  the  intermediate  second  class  students  , attitude and their achievement  in mathematics .

Also, to know the statistical sign

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Publication Date
Tue Sep 06 2022
Journal Name
International Journal Of Professional Business Review
The Relationship Between Audit Services and Non-Audit Actuarial Services in the Auditor’s Report
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Purpose: In view of the trend toward using international financial reporting standards when generating financial statements, we looked at the interaction between audit services and non-audit services for auditors in the context of actuarial services for insurance firms. CPAs are authorized to work in banks and insurance businesses, but those with a practicing license obtained after earning a higher academic degree are not. Design/methodology/approach: A small number of auditing firms control the decisions issued by the Iraqi Accountants Association, monopolizing audit services in banks and insurance businesses. In the case of actuarial services used in reserve estimation, they are credited to an external party's account withou

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Publication Date
Tue Jan 01 2019
Journal Name
Association Of Arab Universities Journal Of Engineering Sciences
Experimental and numerical investigation on the behavior of reinforced reactive powder concrete two-way slabs under static load
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This paper studied the behaviour of reinforced reactive powder concrete (RPC) two-way slabs under static load. The experimental program included testing three simply supported slabs of 1000 mm length, 1000 mm width, and 70 mm thickness. Tested specimens were of identical properties except their steel fibers volume ratio (0.5 %, 1 %, and 1.5 %). Static test results revealed that, increasing steel fibers volume ratio from 0.5% to 1% and from 1% to 1.5%, led to an increase in: first crack load by (32.2 % and 52.3 %), ultimate load by (36.1 % and 17.0 %), ultimate deflection by (33.6 % and 3.4 %), absorbed energy by (128 % and 20.2 %), and the ultimate strain by (1.1 % and 6.73 %). The stiffness and ductility of the specimens also increased. A

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