Recently a special parallel-plate ionization chamber was developed and characterized at the Instituto de Pesquisas Energéticas e Nucleares. The operational tests presented results within the recommended limits. In order to determine the influence of some components of the ionization chamber on its response, Monte Carlo simulations were carried out. The experimental and simulation results pointe...

AIM The aim of this work was to develop multiple-source models for electron beams of the NEPTUN 10PC medical linear accelerator using the BEAMDP computer code. BACKGROUND One of the most accurate techniques of radiotherapy dose calculation is the Monte Carlo (MC) simulation of radiation transport, which requires detailed information of the beam in the form of a phase-space file. The computing...

abstract background: accurate methods of radiation therapy dose calculation. there are different monte carlo codesfor simulation of photons, electrons and the coupled transport of electrons and photons. mcnpis a general purpose monte carlo code that can be used for electron, photon and coupledphoton-electron transport.monte carlo simulation of radiation transport is considered to be one of the ...

OBJECTIVE To demonstrate attenuation of radiation from iodine 125 ((125)I) to intraocular structures using liquid vitreous substitutes. METHODS Four candidate vitreous substitutes were tested for attenuation using empirical measurement and theoretical calculation. In vitro and ex vivo cadaveric dosimetry measurements were obtained with lithium fluoride thermoluminescent dosimeters to demonstr...

Monte Carlo simulations are increasingly used in medical physics. In scintigraphic imaging these simulations are used to model imaging systems and to develop and assess tomographic reconstruction algorithms and correction methods for improved image quantization. In radiotherapy-brachytherapy the goal is to evaluate accurately the dosimetry in complex phantoms and at interfaces of tissue, where ...

Introduction: Monte Carlo calculation method is considered to be the most accurate method for dose calculation in radiotherapy. The purpose of this research is comparison between 6 MV Primus LINAC simulation output with commissioning data using EGSnrc and build a Monte Carlo geometry of 6 MV Primus LINAC as realistically as possible. The BEAMnrc and DOSXYZnrc (EGSnrc package) M...

Background: Stereotactic radiosurgery is an important clinical tool for the treatment of small lesions in the brain, including benign conditions, malignant and localized metastatic tumors. A dosimetry study was performed for Elekta ‘Synergy S ’ as a dedicated Stereotactic radiosurgery unit, capable of generating circular radiation fields with diameters of 1-5 cm at isocentre using the BEAM/EGS4...

introduction: nowadays new radiochromic films have an essential role in radiotherapy dosimetry. properties such as high sensitivity, good reproducibility, high spatial resolution, easy readout and portability have made them attractive for dosimetry, especially in high-dose-gradient regions. material and methods: in this study, electron-beam dose distributions in homogenous and heterogeneous pha...

Reported MOSFET measurements concern mostly external radiotherapy and in vivo dosimetry. In this paper, we apply the technique for absolute dosimetry in the context of HDR brachytherapy using an 192Ir source. Measured radial dose rate distributions in water for different planes perpendicular to the source axis are presented and special attention is paid to the calibration of the R and K type de...

we compare two approaches for a markovian model in flexible manufacturing systems (fmss) using monte carlo simulation. the model which is a development of fazlollahtabar and saidi-mehrabad (2013), considers two features of automated flexible manufacturing systems equipped with automated guided vehicle (agv) namely, the reliability of machines and the reliability of agvs in a multiple agv jobsho...