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.
To get access into the orbital floor 3 paths are commonly used which are transconjunctival, subciliary and subtarsal approaches. Each one of these approaches has its advantages and disadvantages. The study assessed the outcomes of the transconjunctival retroseptal approach, which reflects our experience in this type of surgery. Along 8 years, 26 patients received in the emergency room diagnosed with pure isolated orbital floor fractures, all of them admitted to the maxillofacial surgery department and approached by transconjunctival incision without lateral canthotomy. Three types of complications occurred: laceration of the lower eyelid, injury to the lacrimal system and entropion. All of these complications were managed accordingly with n
... Show MoreAmino and fatty acids in the liver tissue of Uromastyx aegyptius microlepis during the periods of hibernation (December) and activity (May) were estimate by a high performance liquid chromatography, liver of a lizard during the activity and hibernation seasons, contained 18 amino acids, which include, 10 essential amino acids and 8 non-essential amino acids, and the liver in the male lizard contained five fatty acids during each season, the concentration rates of all the amino acids during the activity season were higher than their counterparts during the hibernation season, the total concentrations of essential and non-essential amino acids during the activity season were 19434.8 µg/ml, which was greater than the total concentrations leve
... Show MoreIn this paper, we study the common diskcyclic vectors for a path of diskcyclic operators. In particular, if is a path of diskcyclic operators, we show that under certain conditions the intersection of diskcyclic vectors for theses operators is a dense set.
Surge pressure is supplemental pressure because of the movement of the pipes downward and the swab pressure is the pressure reduction as a result of the drill string's upward movement. Bottom hole pressure is reduced because of swabbing influence. An Investigation showed that the surge pressure has great importance for the circulation loss problem produced by unstable processes in the management pressure drilling (MPD) actions. Through Trip Margin there is an increase in the hydrostatic pressure of mud that compensates for the reduction of bottom pressure due to stop pumping and/or swabbing effect while pulling the pipe out of the hole. This overview shows suggested mathematical/numerical models for simulating surge pressure problems ins
... Show MoreThe present study was designed to find the relation between oxidative stress and
pregnancy. The study used one hundred twenty volunteers (ninety pregnant women
and thirty non-pregnant women). Then pregnant women were divided to three
subgroups according to trimester (first trimester, second trimester and third
trimester). then, some oxidative stress factors (MDA, GSH, catalase and TAC) were
measurement. Biochemical tests showed significant (P<0.05) increase in
malonedialdehyied (MDA) and significant (P<0.05) decrease in Glutathione (GSH),
Catalase (CAT) and total antioxidant capacity (TAC) in pregnant women compared
with non-pregnant women group. It was concluded from this study that the
pregnancy led to
In this paper, the satellite in low Earth orbit (LEO) with atmospheric drag perturbation have been studied, where Newton Raphson method to solve Kepler equation for elliptical orbit (i=63 , e = 0.1and 0.5, Ω =30 , ω =100 ) using a new modified model. Equation of motion solved using 4th order Rang Kutta method to determine the position and velocity component which were used to calculate new orbital elements after time step ) for heights (100, 200, 500 km) with (A/m) =0.00566 m2/kg. The results showed that all orbital elements are varies with time, where (a, e, ω, Ω) are increased while (i and M) are decreased its values during 100 rotations.The satellite will fall to earth faster at the lower height and width using big values for ecce
... Show MoreThe escalating development of technology is one of the distinctive features of the communication environment in the field of sending and receiving satellite broadcasts of television channels in general and Iraqi satellite channels in particular, which contributed to the wide and rapid spread and reaching outside the drawn boundaries and bypassing even natural obstacles, and what is important in this is the communication content that these broadcasts Channels and its impact on the recipient due to the media, cultural, educational and entertainment content it provides, and in our research we will analyze the communication content of the Iraqi satellite channel by choosing one of its dialogue programs that coincided with the events of the l
... Show More2D Electrical Resistivity has been applied at three selecting areas within the study area using Dipole-dipole and Wenner arrays with an a-spacing of 1 m, and the profile length was 120 m for both. The total data points were 4455 reads for Dipole-dipole, and the total data points for Wenner were 2340 reads, and the depth of each array was 15.4 m and 20.2 m, respectively. The 2D inverse results indicate the resistivity anomalies approximately at depth (2 - 7.8) m formed as a weakness zone lies within the quaternary and Injana Formation deposits and interbedded with secondary gypsum and gypcretes. Additionally, the inverse resistivity distribution model demonstrated that the area is impacted by groundwater that is interaction wit
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