Computer simulations were carried out to investigate the dependence of the main perturbation parameters (Sun and Moon attractions, solar radiation pressure, atmosphere drag, and geopotential of Earth) on the orbital behavior of satellite. In this simulation, the Cowell method for accelerations technique was adopted, the equation of motion with perturbation was solved by 4th order Runge-Kutta method with step (1/50000) of period to obtain the state vectors for position and velocity. The results of this simulation have been compared with data that available on TLEs (NORD data in two line elements). The results of state vectors for satellites (Cartosat-2B, Gsat-14 and Spot-6) shows excellent correlation and this is leading us to extend our study for (spot-6) satellite to include the orbital behavior during 13000 periods under the effect of one type of perturbation or all types. The results indicate that all perturbation have clear effect on spot-6 orbit, reduced the perigee and apogee about 3 Km. during 89 days, also the time of period reduced 4.7 sec. Other conclusions present that the perigee angle increases 28.01 degree with any perturbation accept SRP. Furthermore, the geopotential have a big periodic effect but the atmospheric drag have accumulated effect on most orbital elements.
The rotor dynamics generally deals with vibration of rotating structures. For designing rotors of a high speeds, basically its important to take into account the rotor dynamics characteristics. The modeling features for rotor and bearings support flexibility are described in this paper, by taking these characteristics of rotor dynamics features into standard Finite Element Approach (FEA) model. Transient and harmonic analysis procedures have been found by ANSYS, the idea has been presented to deal with critical speed calculation. This papers shows how elements BEAM188 and COMBI214 are used to represent the shaft and bearings, the dynamic stiffness and damping coefficients of journal bearings as a matrices have been found
... Show MoreIn this work, the annual behavior of critical frequency and electron density parameters of the ionosphere have been studied for the years (1989, 2001 and 2014) and (1986, 1996 and 2008) which represent the maximum and minimum of years in the solar cycles (22, 23 and 24) respectively. The annual behavior of (Ne, fo ) parameters have been investigated for different heights of Ionosphere layer (100 -1000) Km. The dataset was created both of critical frequency and electron density parameters by using the international reference ionosphere model (IRI-2016 model). This study showed result that during the maximum solar cycles the values of the (Ne) parameter change with
The implementation of the concept of project scheduling in the organizations generally requires a set of procedures and requirements, So, most important of all is the understanding and knowledge of the tools and techniques which are called the methods of scheduling projects. Consequently, the projects of the municipality administration in the holy governorate of Karbala suffer from the problem of delaying their projects and chaos in the ways of implementation. To provide assistance to this directorate and to demonstrate how to schedule projects using one of the advanced scientific methods that proved their ability to schedule any project and its potential to accelerate the time of completion, as well as ease of use and effectiven
... Show MoreResearch Summary
It highlights the importance of assessing the demand for money function in Iraq through the understanding of the relationship between him and affecting the variables by searching the stability of this function and the extent of their influence in the Iraqi dinar exchange rate in order to know the amount of their contribution to the monetary policies of the Iraqi economy fee, as well as through study behavior of the demand for money function in Iraq and analyze the determinants of the demand for money for the period 1991-2013 and the impact of these determinants in the demand for money in Iraq.
And that the problem that we face is how to estimate the total demand for money in
... Show MoreAbstract
The curriculum is the major effective tool in achieving the goals of
education and society.
Many countries that want to reach the forefront of developed countries
through their curriculum have realized this fact. School text book, the
application assessment for knowing the rang of success or fail of this text
book in achieving the general aims. therefore this study aims at assessing the
principals and techniques of geography text book for fourth secondary class of
literary studying from the teachers point of view according to the fields of the
book, style of material, technical arrangement of the material, ethnical
arrangement the language of the book, style of the material, technical
arrang
The optical detectors which had been used in medical applications, and especially in radioactive treatments, need to be modified studied for the effects of radiations on them. This study included preparation of the MnS thin films in a way that vacuum thermal evaporation process at room temperature 27°C with thickness (400+-10nm) nm and a sedimentation rate of 0.39nm/sec on glass floors. The thin films prepared as a detector and had to be treated with neutron irradiation to examine the results gained from this process. The results decay X-ray (XRD) showed that all the prepared thin films have a multi-crystalline structure with the dominance of the direction (111), the two samples were irradiated with a neutron irradiation source (241Am-9Be)
... Show MoreThis research discusses one of the largest and most important issues of a doctrinal and philosophical dimension at the same time, which is the issue of man’s freedom to choose his actions, and thus his responsibility for those actions, by looking at the nature of these acts, their being and the origin of their creation. He showed that they were created in man by force, and that he was their original creator, and that they were among the creatures of the God Almighty God like others, but they are attributed to man through acquisition. So to the first saying went Jahmiyya or Jabariyya, and to the second saying went to fatalism in the past, and the existentialists shared with them in the modern era, and to the third saying went to the Sun
... Show MoreThis paper is based on the Sentinel-2 satellite data: the thermal, red, and NIR bands. The Babylon city was chosen in this study for different reasons: its location in the middle of Iraq and it represents the largest capitals of the Mesopotamia civilization in the word. The Land Surface Temperature (LST) was determined using a method that incorporates remote sensing, geographic information systems, and statistics. This process has made it possible to monitor the relationship between land usage and the land surface temperature for four seasons in the year 2021. The mapswere processed and analyzed by using ArcGIS software. Five maps of the LST were constructed. Each map represents diffe