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ijs-1261
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
Sat Nov 12 2016
Journal Name
International Journal Of Mechanical Engineering And Technology (ijmet)
PERFORMANCE OF TWO-WAY NESTING TECHNIQUES FOR SHALLOW WATER MODELS
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A new two-way nesting technique is presented for a multiple nested-grid ocean modelling system. The new technique uses explicit center finite difference and leapfrog schemes to exchange information between the different subcomponents of the nested-grid system. The performance of the different nesting techniques is compared, using two independent nested-grid modelling systems. In this paper, a new nesting algorithm is described and some preliminary results are demonstrated. The validity of the nesting method is shown in some problems for the depth averaged of 2D linear shallow water equation.

Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Engineering
Two Stage Evaporative Cooling of Residential Building Using Geothermal Energy
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The weather of Iraq has longer summer season compared with other countries. The ambient temperature during this season reaches over 50 OC which makes the evaporative cooling system suitable for this climate. In present work, the two-stage evaporative cooling system is studied. The first stage is indirect evaporative cooling (IEC) represented by two heat exchangers with the groundwater flow rate (5 L/min). The second stage is direct evaporative cooling (DEC) which represents three pads with groundwater flow rates of (4.5 L/min). The experimental work was conducted in July, August, September, and October in Baghdad. Results showed that overall evaporative efficiency of the system (two coils with three pads each

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Publication Date
Mon Oct 30 2023
Journal Name
Iraqi Journal Of Science
Response of Two Rosa sp. to Light Quality in Vitro.
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     In this study, dark and various light qualities (white, red, green, and blue) were applied to evaluate their effects on growth characteristics, chemical content, and callus characteristics of Rosa damascene Mill. and Rosa hybirda L.

   Explant (single-node and shoot tips) cultured on MS media supplemented with sucrose, agar, and plant growth regulators ( Kin 0.5 mg/l and IBA 1 mg/l for whole plant formation experiment or 1 mg/l kin with 0.5 mg/l IBA for callus experiment), incubated in a growth chamber.

   The results of the whole plant formation experiment showed variation in growth characteristics in two types of Rosa, Green and white light caused the height ratio of shoot growth compared wi

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Publication Date
Sat Jun 30 2018
Journal Name
Journal Inspector General
Some examples of police errors - a comparative study of the scope of civil liability between American and Iraqi laws
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Police play an important role in any society. Where they maintain public order by stopping and deterring crime and bringing criminals to justice. In order to achieve these objectives, they have certain means of law (search, arrest, use of force that may be lethal in some cases). However, such means may be misused in a way that harms members of society such as (Exceeding the Scope of a search warrant, violation of privacy of individuals, False Imprisonment, Excessive use of force, Sudden Deaths in custody, Sexual Assault and Harassment, Failure to respond for Domestic violence calls), which raises the civil liability of police officers and their agencies for such damage. Police officers may even abuse their characteristics even outside offic

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Publication Date
Tue Dec 16 2008
Journal Name
Journal Of Planner And Development
Evaluation of the efficiency of the regional transport network of the district center of Mahmudiya
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The Study aims at evaluating the efficiency of the regional transportation net in Al-mahmoodiya Qadaa center. The bus station of the Qadaa center is suffering from heavy traffic jam, which is due to the ongoing movement of the adjacent provinces, particularly the small cities. They vary in the degree of their link by the regional transportation net that links the province with the centers of big cities. That affects the traffic flow of the civilians of these cities and their daily activities in hierarchical way To achieve the purpose of the study, a questionnaire has been constructed to collect data through selecting a random sample including the passengers who are coming to the bus station in Al-Mahmoodiya center to know the flo

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Publication Date
Sat Jun 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Ridge regression method with some classical methods to estimate the parameters of Lomax distribution by simulation
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Abstract

In this research provide theoretical aspects of one of the most important statistical distributions which it is Lomax, which has many applications in several areas, set of estimation methods was used(MLE,LSE,GWPM) and compare with (RRE) estimation method ,in order to find out best estimation method set of simulation experiment (36) with many replications  in order  to get mean square error and used it to make compare , simulation experiment  contrast with (estimation method, sample size ,value of location and shape parameter) results show that estimation method effected by simulation experiment factors and ability of using other estimation methods such as(Shrinkage, jackknif

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Publication Date
Mon May 15 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Determination of the Heavy Metals in the Contaminated Soil Zones at College of Education Ibn Al-Haitham -University of Baghdad
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  Soil is a crucial component of environment. Total soil analysis may give information about possible enrichment of the soil with heavy metals. Heavy metals, potentially contaminate soils, may have been dumped on the ground. The concentrations of soil heavy metals (Cd, As, Pb, Cr, Ni, Zn and Cu) were measured in three zones thought to be deeply contaminated at different depths (5, 25, 50 cm) at Ibn Al-Haitham College. The highest concentration of heavy metals Pb (63.3ppm), Cr (90.7ppm), Ni (124ppm) and Cu (75.7ppm) were found in zone (A) location-1, where the highest concentration of Zn (111.7ppm) was found in zone (C). Cd and As were detected in small amounts in all zones.     PH value, organic matters, carbonat

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Publication Date
Wed Jan 19 2022
Journal Name
Iraqi Journal Of Science
Determination of Some Oxidative Stress Parameters and Antioxidants in Sample of Iraqi Beta Thalassemia Major Patients
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Repeated blood transfusion in beta thalassemia major patients may lead to peroxidative tissue injury by secondary iron overload. In the present study, 100 patients(50 male+50 female) with beta thalassemia major patients with age (5-20) years and 60 healthy control were included during their attendance at Abin Al_Baladi hospital in Baghdad. Malondialdehyde ,Superoxide Dismutase and Vitamin E, were measured by using kits.The results showed A highly significant (p<0.01)increase in the levels of Malondialdehyde and Superoxide Dismutase, whereas, significant p(<0.01)decrease in the levels of vitamin-E, This suggest that oxidative stress and reduced antioxidant defense mechanism play an important role in pathogenesis of beta thalassemia

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Publication Date
Tue Jan 18 2022
Journal Name
Iraqi Journal Of Science
Determination of Porosity and Permeability of Darnah Formation at Al-Jabal Al-Akhdar-North Eastern Libya
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The study area is located at AL Jabal AL-Akhdar region North Eastern part of Libya. The study includes (23) fresh samples that are taken from Darnah limestone Formation, these samples were distributed on and covered about (210) km2. The porosities and permeabilities of these samples were determined. This study is important because this formation is considered as a good reservoir for hydrocarbon accumulation in other places in Libya.
The porosity was measured by three different methods namely by porosimeter (using core samples), thin sections and binocular microscope. The permeability are also measured by two methods, the first method was by Nitrogen method and the other is by Klinkenberg method. The instrument that used for measuring

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Publication Date
Sun Jul 02 2023
Journal Name
Iraqi Journal Of Science
Determination of Uranium Concentration in Soil of Baghdad Governorate and its Effect on Mitotic Index Assay
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The aim of this work is to determine the uranium concentration in soil samples
taken from the north, south, east, west and center of the city of Baghdad and
measure its impact on the rate of cell division for non-smokers peoples and living in
those areas and that between the ages 25-30 year.
The uranium concentration in the samples determined by using CR-39 track
detector . As calculated for the ten samples of each site when irradiated by thermal
neutrons from the (Am - Be) source with flux (5x 103 n S-1cm-2), the concentration
values were calculated by a comparison with standard geological samples. The
results indicate that the extent of the concentration of uranium in the soil north and
east of Baghdad was 12

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