background: the monte carlo method is the most accurate method for simulation of radiation therapy equipment. the linear accelerators are currently the most widely used machines in radiation therapy centers. methods: in this work, a monte carlo modelling of the siemens oncor linear accelerator in 6 mv and 18 mv beams was performed. the results of simulation were validated by measurements in wat...

We develop and demonstrate the capability of a high order accurate finite difference weighted essentially non-oscillatory (WENO) solver for the direct numerical simulation of transients for a two space dimensional Boltzmann transport equation (BTE) coupled with the Poisson equation modeling semiconductor devices such as the MESFET and MOSFET. We compare the simulation results with those obtaine...

Sequential Monte Carlo is a family of algorithms for sampling from a sequence of distributions. Some of these algorithms, such as particle filters, are widely used in the physics and signal processing researches. More recent developments have established their application in more general inference problems such as Bayesian modeling. These algorithms have attracted considerable attentions in rec...

This paper serves as an introductory review of Brownian Dynamics (BD), Molecular Dynamics (MD), and Monte Carlo (MC) modeling techniques. These three simulation methods have proven to be exceptional investigative solutions for probing discrete molecular, ionic, and colloidal motions at their basic microscopic levels. The review offers a general study of the classical theories and algorithms tha...

Probabilistic modeling provides the capability to represent and manipulate uncertainty in data, models, decisions and predictions. We are concerned with the problem of learning probabilistic models of dynamical systems from measured data. Specifically, we consider learning of probabilistic nonlinear state space models. There is no closedform solution available for this problem, implying that we...

Background: Monte Carlo and experimental relative dose determination in a water phantom, due to a high dose rate (HDR) 192Ir source is presented for real energy spectrum and monochromatic at 356 keV. Materials and Methods: The dose distribution has been calculated around the 192Ir located in the center of 30 cm ×30 cm ×30 cm water phantom using MCNP4C code by Monte Carlo method. Relati...

Background: Iodine brachytherapy sources with low photon energies have been widely used in treating cancerous tumors. Dosimetric parameters of brachytherapy sources should be determined according to AAPM TG-43U1 recommendations before clinical use. Monte Carlo codes are reliable tools in calculation of these parameters for brachytherapy sources. Materials and Methods: Dosimetric param...

It is shown that Bayesian inference from data modeled by a mixture distribution can feasibly be performed via Monte Carlo simulation. This method exhibits the true Bayesian predictive distribution, implicitly integrating over the entire underlying parameter space. An innnite number of mixture components can be accommodated without diiculty, using a prior distribution for mixing proportions that...

background: monte carlo method (mc) has played an important role in design and optimization of medical linacs head and beam modeling. the purpose of this study was to compare photon beam features of two commercial linacs, varian 21ex and elekta sl-25 using mcnp4c mc code. materials and methods: the 6mv photon beams of varian 21ex and elekta sl-25 linacs were simulated based on manufacturers pro...