background: the aim of this study was to investigate clinical applications of mobile c-arms and consequent radiation risk,to increase medical attention on radiation protection, and to provide basic data for safe radiation use in the operating room. materials and methods: in this study, a total of 374 surgical operations, conducted using a portable fluoroscopic x-ray system from january to march...

introduction the purpose of this study was to estimate organ and effective doses in patients undergoing some common x-ray examinations in sabzevar, iran. the effective dose is one of the best parameters for describing the amount of radiation dose received by a patient undergoing any diagnostic x-ray examination. the public dose from x-ray examinations depends on various factors, and its contrib...

ct.scan examinations cause high patient absorbed dose from x-ray ionizing radiation. therefore it is necessary to obtain superficial dose profile in z-line. in this research 11 thermoluminecent dosimeter (tld), after calibration were located on z line perpendicular to slice thickness. ct.scan machines did x-ray exposures. the resultant dose profiles showed gussian shape apperience, which has se...

background: a study has been conducted to assess two useful radiation protection indices, the annual per-capita effective dose equivalent (aed) and the genetically significant dose (gsd), from conventional diagnostic radiography in 10 counties with more than 1,886,000 inhabitants in khorasan province in iran. materials and methods: the health centre authorities of khorasan province were asked t...

background: radiation dose knowledge through xray examinations and their distribution in iran provides useful guidance on patient dose reduction. the results of the entrance skin dose (esds) of five common radiographies in all radiology centers in yazd province were reported in our previous study (2003). in the present study we have evaluated the collective effective dose of conventional x-ray ...

background: with the introduction of computed tomography in diagnostic radiology a new and fundamentally different imaging modality has become available. meanwhile, it is clear that the absorbed doses by the patients during ct were relatively high in comparison with those of other diagnostic radiology techniques. the aim of this survey was to determine the average absorbed dose in yazd province...

Recent years witnessed several advances in developing multi-goal conversational recommender systems (MG-CRS) that can proactively attract users’ interests and naturally lead user-engaged dialogues with multiple goals diverse topics. Four tasks are often involved MG-CRS, including Goal Planning, Topic Prediction, Item Recommendation, Response Generation. Most existing studies address only some o...

background: the assessment of rbe quantity in the treatment of cancer tumors with proton beams in treatment planning systems (tps) is of high significance. given the significance of the issue and the studies conducted in the literature, this quantity is fixed and is taken as equal to 1.1. objective: the main objective of this study was to assess rbe quantity of proton beams and their variations...

introduction intensity-modulated radiotherapy (imrt) is becoming an increasingly routine treatment method. imrt can be delivered by use of conventional multileaf collimators (mlcs) and/or physical compensators. one of the most important factors in selecting an appropriate imrt technique is integral dose. integral dose is equal to the mean energy deposited in the total irradiated volume of the p...

Electromagnets have traditionally been used in all drives. Because they take up space, the size of machine grows tandem with increased torque and it’s rating thereby lowering its energy efficiency. If rotor winding is replaced permanent magnets, motor will reverse. The recent improvement magnetic materials resulted a reduction more effective use redial space. Permanent Magnet Synchronous Motors...