A new Markov Chain Monte Carlo algorithm that allows parallel processing has been described in a previous paper (“Markov Chain Monte Carlo Calculations Allowing Parallel Processing Using a Variant of the Metropolis Algorithm”) that appeared in this journal in 2010. In this second follow-on paper, the problem of calculating the normalization integral of the distribution function is considered. I...

This paper presents an enhanced transillumination radiosity method that can provide accurate solutions at relatively low computational cost. The proposed algorithm breaks down the double integral of the gathered power to an area integral that is computed analytically and to a directional integral that is evaluated by quasi-Monte Carlo or Monte-Carlo techniques. The paper also analyses the requi...

This paper presents the Monte Carlo simulation of the Positron Emission Tomography (PET) scanning technique using MCNPX code. The raw data generated by general MCNPX code contain a lot of unnecessary information for the image reconstruction process. This requires a large memory to store all this information. In order to reduce the needed memory, we introduce some modifications on the MCNPX code...

We consider noise in computed tomography images that are reconstructed using the classical direct fan-beam filtered backprojection algorithm, from both fulland short-scan data. A new, accurate method for computing image covariance is presented. The utility of the new covariance method is demonstrated by its application to the implementation of a channelized Hotelling observer for a lesion detec...

Monte Carlo Algorithms for Solving Fredholm Integral Equations and Fredholm Differential Integral Equations Behrouz Fathi Vajargah and Mojtaba Moradi Department of Mathematics Guilan University, Rasht, Iran [email protected], [email protected] Abstract In this paper we establish a new algorithm for solving non linear differential integral equations based on Monte Carlo methods. For obta...

Detecting cancerous lesion is an important task in positron emission tomography (PET). Bayesian methods based on the maximum a posteriori principle (also called penalized maximum likelihood methods) have been developed to deal with the low signal to noise ratio in the emission data. Similar to the filter cut-off frequency in the filtered backprojection method, the prior parameters in Bayesian r...

New fast detector technology has driven significant renewed interest in time-resolved measurement of early photons in improving imaging resolution in diffuse optical tomography and fluorescence mediated tomography in recent years. In practice, selection of early photons results in significantly narrower instrument photon density sensitivity functions (PDSFs) than the continuous wave case, resul...

A Monte Carlo simulation using the PRESTA version of the EGS4 code has been employed as an investigative tool to calculate the absorbed dose in water close to 192Ir wire implants. It has been shown that a treatment planning system, such as GE Target II, using the Sievert integral and the Meisberger polynomial is only able to reproduce the Monte Carlo results at radial distances of 1 mm and fart...