m. haghparast

Ionizing radiation is present in all environment of the Earth’s surface, beneath the Earth and in the atmosphere. Human beings are exposed to external radiation from their surroundings naturally and also to internal radiation from food, water and air they consume. Then, it is important to measure and develop knowledge about radiation.

This study is designed to evaluate the risks of radiation outdoors and indoors and in hot spring in Gachine area of Bandar Abbas.

The device used in this cross sectional study was environmental radiation surveymeter. Indoor gamma radiation in Gachine area was carried out inside 115 dwellings. Measurement for hot spring waters was carried out at one meter above water level. Dose rates were recorded for an hour.

Our results indicate the outdoor dose rate gamma radiation in Gachine area is higher than the global mean dose rate. Moreover, Gachine Bala has the highest outdoor gamma radiation (78.87 nGy/h) and Gachine Paien has the lowest gamma background radiation (71.62 nGy/h).

This study demonstrates that indoor mean dose rate of gamma radiation in this area is higher than the global mean dose rate. Estimated indoor mean dose rates were for Gachine Paien (110.58 nGy/h), Gachine Bala (111.83 nGy/h), Ship industry dwelling (109.30 nGy/h) and Jamal Ahmad (107.84 nGy/h). The highest dose rate above hot spring was obtained from Chostaneh (1320 nGy/h).

In this paper predicting of position of satellite based on extended kalman filter with considering hardware implementation consideration and simultaneously maintaining desired accuracy is investigated. For this purpose, first, effective forces on orbital dynamic and nonlinear equation of orbital motion are presented. In order to increasing accuracy of prediction in position of satellite, J2, J3 and J4 harmonics of potential function of the earth are considered and future position of satellite is predicted using linearized dynamic model and applying EKF on this model. Here Measurement data are position and velocity vector of satellite which are extracted by GPS receivers. Since in this paper systematic satellite design is considered, scenario of “ON TIME” of GPS receivers based on power consumption considerations is discussed. Finally simulation results for a LEO satellite and comparing these results with STK results, shows accuracy of presented modeling and equations.

Traumatic brain injury (TBI) is one of the most common causes of seizure and about 10% of patients with severe and moderate trauma develop seizure. Phenytoin is an anti-seizure medicine which is widely prescribed to prevent seizure in TBI patients. Even it has non-linear pharmacokinetics in therapeutic concentrations, the prescription of which necessitates continuous evaluation of plasmatic level of medicine and regulating the dosage.

This study aimed at surveying the variability of Phenytoin serum level in TBI patients in Poursina Teaching Hospital to determine the dosage of medicine more precisely to reach the Prophylactic level.

In a descriptive longitudinal study, 90 patients of Trauma Ward of Poursina Hospital were studied. Phenytoin serum level was estimated in first, second, and seventh day after hospitalization by using RAN DOX kits, the results were then analyzed by SPSS software (ver16). Exact Test, Fisher, and Pearson T-test were utilized to analyze the data.

Out of 90 studied patients, 79 (87.7%) were men and 11(12.3%) women. Mean age was estimated 36.3±15.6 for men and 41.7±16 for women. There was no significant difference between the Phenytoin level in first and third day in two groups. The Phenytoin serum level in 24 first hrs didn’t reach therapeutic level in 75.6% of patients. The average of Phenytoin serum level was in therapeutic level in third day and Phenytoin serum level didn’t reach therapeutic level only in 5% of patients (p≥0.05). This average figure was 20-30 mg/dl in more than half of the patients on seventh day, during which all patients reached therapeutic level (p≥0.05). A significant relationship was observed between age and Phenytoin serum level in all three levels (p<0.05).

Phenytoin is considered as an anti-seizure medicine which is vastly used in TBI victims. Using Phenytion requires exact monitoring due to its limited therapeutic range and linear pharmacokinetics. Since the changes of medicine dosage can lead to blood poisoning and make the medicine ineffective, its prescription needs much more attention regarding its gender, age, and needed dosage.

A Fault Tolerant attitude control system has been designed in this paper, which provides abilities of fault detection, identification and recovery. For this purpose, nonlinear dynamics of satellite is modeled based on Takagi-Sugeno method, which enables us to extend advantages of linear adaptive observer for nonlinear dynamics of satellite. In the designed adaptive observer, occurrence of fault in satellite reaction wheels are estimated based on an adaptive law which provides abilities of fault detection and identification in these actuators. Also, a back stepping feedback linearization control law has been applied for recovery which uses estimated fault term provided by adaptive observer as a compensation term in control law. So, bounded error of attitude control has been guaranteed even in faulty conditions. Finally, fault detection, identification and recovery algorithms have been verified by simulation results.