This study proposes robust means modeling (RMM) approaches for hypothesis testing of mean differences for between-subjects designs in order to control the biasing effects of nonnormality and variance inequality. Drawing from structural equation modeling (SEM), the RMM approaches make no assumption of variance homogeneity and employ robust estimation/rescaling strategies in order to alleviate re...

background: because of the adverse effects of ionizing radiation on fetuses, prior to radiotherapy of pregnant patients, fetal dose should be estimated. fetal dose has been studied by several authors in different depths in phantoms with various abdomen thicknesses (at). in this study, the effect of maternal at and depth in fetal dosimetry was investigated, using peripheral dose (pd) distributio...

introduction: the key characteristics of positron emission tomography (pet) are its quantitative capability and its sensitivity, which allow the in vivo imaging of biochemical interactions with small amounts of tracer concentrations. therefore, accurate quantification is important. however, it can be sensitive to several physical factors. the aim of this investigation is the assessment of the e...

conclusions according to the results, the old dosimetry formalisms, overestimate the dose especially towards the applicator’s tip. while the tg-43u1 based software perform the calculations more accurately. results for a typical arrangement of 10 active pellets in the applicator, the percentage difference between doses obtained by the new algorithm at 1cm distance from the tip of the applicator ...

large quantities of radiopharmaceuticals prescribed for treatment and diagnosis are excreted through kidney. therefore, radiation unwanted dose is created in kidney. as a result, exact calculation of prescribed radiopharmaceuticals amount is important. monte carlo method is used for simulation of radiation transport in body due to random nature of radiation. in this research, for the first time...

the interaction between the solute and the solsent molecules play a crucial role in understanding the various molecular processes involved in chemistry and biochemistry, so in this work the potential energy of active site of azurin have been calculated in solvent by the monte carlo simulation. in this paper we present quantitative results of monte carlo calculations of potential energies of ...

for superficial lesions, the electrons may be used for radiation therapy. the high energy photons and electrons are produced by a linear accelerator (linac).   many of electron fields need the shielding of normal or critical organs. the electron shields are usually lead slabs with few millimeter thickness which should be placed near the skin, less than 1 centimeter away from skin. in the inspec...

introduction after the publication of task group number 43 dose calculation formalism by the american association of physicists in medicine (aapm), this method has been known as the most common dose calculation method in brachytherapy treatment planning. in this formalism, the water phantom is introduced as the reference dosimetry phantom, while the attenuation coefficient of the sources in the...

In this paper we propose a new Bayesian approach to data modelling. The Bayesian partition model constructs arbitrarily complex regression and classiication surfaces over the design space by splitting the space into an unknown number of disjoint regions. Within each region the data is assumed to be exchangeable and to come from some simple distribution. Using conjugate priors the marginal likel...

Modeling consumer heterogeneity helps practitioners understand market structures and devise effective marketing strategies. In this research the authors study finite mixture specifications for modeling consumer heterogeneity when each regression coefficient has its own finite mixture, that is, an attribute finite mixture model. An important challenge of such an approach to modeling heterogeneit...