background: megavoltage beams used in radiotherapy are contaminated with secondary electrons. different parts of linac head and air above patient act as a source of this contamination. this contamination can increase damage to skin and subcutaneous tissue during radiotherapy.  monte carlo simulation is an accurate method for dose calculation in medical dosimetry and has an important role in opt...

introduction: due to the large number of pet systems available in the market, it is not very easy to decide about the scanner of choice. conducting a research in order to compare all different pet scanners is very time consuming and expensive and practically impossible. however, such comparison may be conducted using pet simulators. in this study, the performance of 6 different pet scanners in ...

background: recent pre-clinical and clinical studies indicate that irradiation in the dose range of 15 to 30 gy can reduce rate of restenosis in patients who have undergone an angioplasty. the use of filled balloon with radioactive solution was proposed as one of the possible intravascular irradiation techniques. materials and methods: the monte carlo n-particle transport code (mcnp4b) was used...

The Monte Carlo method has been successfully used for computing the extreme (largest and smallest in magnitude) eigenvalues of matrices. In this paper we study computing eigenvectors as well with the Monte Carlo approach. We propose and study a Monte Carlo method based on applying the ergodic theorem and compare the results with those produced by a Monte Carlo version of the power method. We al...

A description of Monte Carlo methods for simulation of proteins is given. Advantages and disadvantages of the Monte Carlo approach are presented. The theoretical basis for calculating equilibrium properties of biological molecules by the Monte Carlo method is presented. Some of the standard and some of the more recent ways of performing Monte Carlo on proteins are presented. A discussion of the...

The radiance equation, which describes the global illumination problem in computer graphics, is a high dimensional integral equation. Estimates of the solution are usually computed on the basis of Monte Carlo methods. In this paper we propose and investigate quasi-Monte Carlo methods, which means that we replace (pseudo-) random samples by low discrepancy sequences, yielding deterministic algor...

" Extended Ensemble Monte Carlo " is a generic term that indicates a set of algorithms which are now being popular in a variety of fields in physics and statistical information processing. Exchange Monte Carlo (Metropolis-Coupled Chain, Parallel Tempering), Simulated Tempering (Expanded Ensemble Monte Carlo), and Multicanonical Monte Carlo (Adaptive Umbrella Sampling) are typical members of thi...