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An Optimum Strategy for Producing Precise GPS Satellite Orbits using Double-Differenced Observations
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Both the double-differenced and zero-differenced GNSS positioning strategies have been widely used by the geodesists for different geodetic applications which are demanded for reliable and precise positions. A closer inspection of the requirements of these two GNSS positioning techniques, the zero-differenced positioning, which is known as Precise Point Positioning (PPP), has gained a special importance due to three main reasons. Firstly, the effective applications of PPP for geodetic purposes and precise applications depend entirely on the availability of the precise satellite products which consist of precise satellite orbital elements, precise satellite clock corrections, and Earth orientation parameters. Secondly, the PPP processing strategy has been employed by the International GNSS Service (IGS) and IGS analysis centers to evaluate their products in terms of homogeneity and precision over a long period of time. Thirdly, the precise positions, which are determined using PPP technique, and are referenced directly to the geodetic reference frame of the satellite orbital parameters. Thus, the definition of the geodetic datum of the site coordinates using different strategies plays an enormous role in the process of generation satellite orbital parameters which have to be compatible with the corresponding satellite clock corrections and the Earth orientation parameters. This study focuses on producing uninterrupted series of satellite orbit and clock products using different criteria and assesses these products using PPP. The double-difference processing technique was used to achieve the goal of this study by Bernese GPS software version 5.0. Twenty-two globally distributed IGS stations were selected to run PPP based on the generated products and then compare the results with corresponding PPP results which were created based on the IGS rapid products. The comparison pointed to a significant improvement in the generated precise products which have considerably increased the precision of positions. What is more, this study stated that there is an observable agreement between the horizontal positions accuracies which are generated using different techniques for modeling the reference frame.

 

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Publication Date
Sat Jan 13 2018
Journal Name
Journal Of Engineering
Producing Coordinate Time Series for Iraq's CORS Site for Detection Geophysical Phenomena
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Global Navigation Satellite Systems (GNSS) have become an integral part of wide range of applications. One of these applications of GNSS is implementation of the cellular phone to locate the position of users and this technology has been employed in social media applications. Moreover, GNSS have been effectively employed in transportation, GIS, mobile satellite communications, and etc. On the other hand, the geomatics sciences use the GNSS for many practical and scientific applications such as surveying and mapping and monitoring, etc.

In this study, the GNSS raw data of ISER CORS, which is located in the North of Iraq, are processed and analyzed to build up coordinate time series for the purpose of detection the

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Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Physics
Lineament automatic extraction analysis for Galal Badra river basin using Landsat 8 satellite image
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This research including lineament automated extraction by using PCI Geomatica program, depending on satellite image and lineament analysis by using GIS program. Analysis included density analysis, length density analysis and intersection density analysis. When calculate the slope map for the study area, found the relationship between the slope and lineament density.
The lineament density increases in the regions that have high values for the slope, show that lineament play an important role in the classification process as it isolates the class for the other were observed in Iranian territory, clearly, also show that one of the lineament hit shoulders of Galal Badra dam and the surrounding areas dam. So should take into consideration

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Publication Date
Fri Jun 24 2022
Journal Name
Iraqi Journal Of Science
Optimum conditions for fibrinolytic enzyme (Nattokinase) production by Bacillus sp. B24 using solid state fermentation
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The present study was aimed to screen the ability of local isolates of Bacillus spp. (56 isolates) for nattokinase production using solid state fermentation, then optimize the nutritional conditions for enzyme production. The isolates were subjected to the primary and secondary screening process to select the Bacillus isolate which give the highest production of enzyme. It was found that Bacillus sp. B24 had the highest productivity of the enzyme (25.58U/mg protein). The optimum conditions for nattokinase production were performed by the solid state fermentation and found that the wheat bran was the best medium at initial moisture ratio 1.0:1.0 (w/v) using distilled water as moisturizing solution with initial pH of 7.0 after inoculation

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Publication Date
Thu Dec 01 2011
Journal Name
Iraqi Journal Of Physics
Multilayer Perceptron for analyzing satellite data
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Different ANN architectures of MLP have been trained by BP and used to analyze Landsat TM images. Two different approaches have been applied for training: an ordinary approach (for one hidden layer M-H1-L & two hidden layers M-H1-H2-L) and one-against-all strategy (for one hidden layer (M-H1-1)xL, & two hidden layers (M-H1-H2-1)xL). Classification accuracy up to 90% has been achieved using one-against-all strategy with two hidden layers architecture. The performance of one-against-all approach is slightly better than the ordinary approach

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Publication Date
Mon Jan 27 2020
Journal Name
Iraqi Journal Of Science
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

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Publication Date
Thu Jan 01 2015
Journal Name
Al–bahith Al–a'alami
News coverage of Arab revolutions in satellite channels An analytical study of the news bulletins in Al - Tijah satellite channel
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The news media material to any means of mass media, and increasingly

 important in TV; what the associated word and image effects, which do different cover events (political, economic, sports, and social .... etc.) directly from the event site and gather the news and do prepared formulation and arranged within the framework provided by the newsletter, as it requires the viewer to provide the public with information about this news correlated; to achieve the greatest gravity following the shapes and styles and technical fees (Alkraveks) during the submission. What we are witnessing today from technological developments help existing staff to cover the news activity quickly and efficiently prohibitivel

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Publication Date
Mon Jan 30 2023
Journal Name
Iraqi Journal Of Science
Complete (k,r)-Caps From Orbits In PG(3,11)
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      The purpose of this article is to partition PG(3,11) into orbits. These orbits are studied from the view of caps using the subgroups of PGL(4,11) which are determined by nontrivial positive divisors of the order of PG(3,11). The τ_i-distribution and c_i-distribution are also founded for each cap.

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Publication Date
Fri Feb 28 2020
Journal Name
Iraqi Journal Of Science
Analytical Study of Earth Tides on Low Orbits Satellites
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     The main objective of this paper is to calculate the perturbations of tide effect on LEO's satellites . In order to achieve this goal, the changes in the orbital elements which include the semi major axis (a) eccentricity (e) inclination , right ascension of ascending nodes ( ), and fifth element argument of perigee ( ) must be employed. In the absence of perturbations, these element remain constant. The results show that the effect of tidal perturbation on the orbital elements depends on the inclination of the satellite orbit. The variation in the ratio  decreases with increasing the inclination of satellite, while it increases with increasing the time.

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Publication Date
Fri Dec 29 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Optimum Time Schedule for Industrial Processes (II)
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The  present study  deals  with successive  stages  of  productive

operations happened to produce a production within each stage befo re it  moves to the next one. ll cou ld  be deduced that this study is an extension  to what bas  been mentioned  in (1 ) .ln  (I),  the  optimum distribution of  di!Terent jobs of  workers and  machines  in  the productive operations has been st ud ied whi le the study  invol ves the optimum schedule for the succession of these operations presuming that thay have already been distributed on machines and workers (2).A mathematical form has been put for this study to define the "Object.ive Function "

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Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Producing High Purity of Metal Oxide Nano Structural Using Simple Chemical Method
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