This paper presents a set of linearized equations was derived for the motion, relative to an elliptical reference orbit, of an object influenced by J2 perturbation terms. Approximate solution for simulations was used to compare these equations and the linearized keplerian equations to the exact equations. The inclusion of the linearized perturbations in the derived equations increased the high ...

purpose : to report a patient with orbital tuberculosis (tb) without any history of systemic involvement case report : a 41-year-old afghani man who presented with progressive painless swelling in lateral side of the left upper eyelid and diplopia. he did not have history of fever or pulmonary disease. histopathology revealed a granulomatous inflammation with caseation necrosis. microbiological...

purpose : we describe clinical and radiologic findings and surgical outcome of an orbital dermoid cyst located in the superior oblique muscle tendon. this unusual location for dermoid tumors has not been reported previously. case report : a 15-year-old girl referred to us with an orbital mass in superonasal quadrant of the left orbit reportedly to be present from birth. computed tomography reve...

Gliosarcoma is an uncommon variant of glioblastoma, which commonly demonstrates dural attachment. However, skull base invasion is rarely seen with this entity. Herein, we report a 44-year-old female patient diagnosed with primary intracranial gliosarcoma extensively invading the skull base and muscles of mastication. She presented to our institution with a three-month history of difficult right...

The purpose of this rersearch is to analyze the effective application of particular earth orbits in dynamical modeling of relative motion problem between two spacecraft. One challenge in implementing these motions is maintaining the relations as it experiences orbital perturbations (zonal harmonics J2 and J3), most notably due to the Earth’s oblateness. Certain aspects of the orbital geometry c...

The study of differential equations is useful in to analyze the possible past or future with help of present information. In this paper, the behavior of solutions has been analyzed around the equilibrium points for Gause model. Finally, some results are worked out to exist the stable periodic orbit for mentioned predator-prey system.

Time evolution of wave packets built from the eigenstates of the Dirac equation for a hydrogenic system is considered. We investigate the space and spin motion of wave packets which, in the non-relativistic limit, are stationary states with a probability density distributed uniformly along the classical, elliptical orbit (elliptic WP). We show that the precession of such a WP, due to relativist...

Given the initial position and velocity of an object, such as a satellite in orbit around the Earth, it is possible to determine its position and velocity at any other time by integrating the equations of motion. This prediction method is called propagating. Specifying the position and velocity of the satellite at a specific time, called the epoch, is a common way of representing an orbit. In t...

purpose: to present the success of novel method for management of conjunctival orbital inclusion cysts following enucleation after using trichloroacetic acid injection technique. methods: a 20% tca solution was injected to treat 6 cases of orbital conjuctival cyst in anophthalmic socket. results: all the patients were treated successfully. the follow-up interval was 1-7 years. no recurrence or ...