monte carlo methods designed base on stochastic reiterations and can be useful in uncertainty conditions. the purpose of this research was investigation of uncertainty to rank desertification indicators. in order to decrease uncertainty have been applied monte carlo reiterations for each value of indicator, if rank of xi is higher than rank of xk constantly. using multi dimension integrals the ...

introduction: in single photon emission computed tomography (spect), the projection data used for image reconstruction are distorted by several factors, including attenuation and scattering of gamma rays, collimator structure, data acquisition method, organ motion, and washout of radiopharmaceuticals. all these make reconstruction of a quantitative spect image very difficult. simulation of a sp...

background: pregnant women are sometimes exposed to ionizing radiation in radiology examinations for various reasons. in such cases, the radiation dose to the conceptus and subsequent risks should be estimated. objective: the purpose of this study was the calculation and presentation of fetal dose and subsequent risks resulted from different x-ray examinations. materials and methods: an analyti...

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...

the determination of gyration radius is a strong research for configuration of a macromolecule. italso reflects molecular compactness shape. in this work, to characterize the behavior of theprotein, we observe quantities such as the radius of gyration and the average energy. we studiedthe changes of these factors as a function of temperature for acetylcholine receptor protein in gasphase with n...

the hydration of biomolecules is vitally important in molecular biology, so in this paper thesolvation energy and radial distribution function of dna bases have been calculated by themonte carlo simulation.the geometries of isolated adenine, guanine, cytosine, and thyminehave been optimized using 6-31+g(d,p) basis function sets. these geometries then will be used inthe monte carlo calculation o...

introduction : due to the importance of laser light penetration and propagation in biological tissues, many researchers have proposed several numerical methods such as monte carlo, finite element and green function methods. among them, the monte carlo method is an accurate method which can be applied for different tissues. however, because of its statistical nature, monte carlo simulation requi...

in this paper, the pricing of a european call option on the underlying asset is performed by using a monte carlo method, one of the powerful simulation methods, where the price development of the asset is simulated and value of the claim is computed in terms of an expected value. the proposed approach, applied in monte carlo simulation, is based on the black-scholes equation which generally def...