Background: The heterogeneous composition of the human body presents numerous tissue types and cavities with widely differing radiologic properties. The aim of the present work was to develop a low cost homogeneous and heterogeneous phantom and the absorbed dose were measured by ionization chamber for different radiotherapy treatment techniques and compared with treatment planning syst...

The appropriate evaluation of measured doses in mixed fi elds requires the calibration of dosimeters in relation to different types of radiation and exposure conditions in order to split the signal into individual components corresponding to the specifi c radiation and exposure conditions of the entire period and evaluate the critical level, lower limit of detection and corresponding uncertaint...

obtaining temperature distribution data of slabs under rolling is essential as the mechanical and metallurgical properties of the metal under this process vary with temperature. using the control volume method, a mathematical model is employed in this study to predict slab temperature in the hot roll process at mobarakeh steel company. the effects of different parameters including the heat resu...

background: the purpose of this study is to fabricate inexpensive in-house low cost homogeneous and heterogeneous human equivalent thorax phantom and assess the dose accuracy of the treatment planning systems (tps) calculated values for different lung treatment dosimetery. it is compared with thermoluminescent dosimeter (tld) measurement. materials and methods: homogeneous and heterogeneous tho...

In order to improve the fat suppression performance of in vivo (13)C-MRS operating at 3.0 Tesla, a phantom model study was conducted using a combination of two fat suppression techniques; a set of pulses for frequency (chemical shift) selective suppression (CHESS), and spatial saturation (SAT). By optimizing the slab thickness for SAT and the irradiation bandwidth for CHESS, the signals of the ...

background: this study assessed the clinical usefulness of the solid phantom, which may compensate for the disadvantages of the water phantom, by comparing the radiological doses between the two depending on their depths. materials and methods: the experimental equipment used was a linear accelerator for medical use, water phantom, solid phantom, farmer type ion chamber and electrometer. the di...

Background Time resolved phase contrast imaging is hardly used in small animal studies due to a lack of signal-to-noise ratio. Some studies were performed in 2D and one publication (Janiczek et al, MRM 2011) reported flow measurement in mouse aortic arch in 3D due to the use of a thin excitation slab and high Time-Of-Flight (TOF) effect. However, this strategy is not applicable on the whole car...

AIM Complex geometry of breast tissue causes perturbation in dose distribution. This problem can beget overdose or under-dose points in match region of three fields. The aim of this study is to create dose homogeneity distribution in match region between tangential and supraclavicular fields (SCF) with Gafchromic external beam therapy (EBT) film. MATERIALS AND METHODS In this study, an anatom...

PURPOSE It is essential to assess the lung dose during TBI to reduce toxicity. Here we characterize the accuracy of the AAA and Acuros algorithms when using cerrobend lung shielding blocks at an extended distance for TBI. METHODS We positioned a 30×30×30 cm3 solid water slab phantom at 400 cm SSD and measured PDDs (Exradin A12 and PTW parallel plate ion chambers). A 2 cm thick, 10×10 cm2 cerr...

This study presents the results of an experimental program to investigate the effectiveness of an innovative combined FRP technique using combination of externally bonded (EB) FRP fabrics and near surface mounted (NSM) FRP rods for flexural strengthening of existing reinforced concrete (RC) two-wayslabs with low clear cover thickness. Three full-scale RC slabs (1500×1500×120 mm) were tested und...