Differential Die-Away Analysis (DDAA) is a very effective technique for detection of special nuclear material (SNM). It is based on fission neutrons that are detected with a time constant characteristic of the thermal neutron that created them. The presence of fast neutrons with this slow die-away time is a positive indication of the presence of SNM in the inspected cargo. Results are presented...

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...

Experimental simulation to a line source has been realized at FNS, JAERI, within the USDOE/JAERI collaborative Program on Fusion Neutronics. This simulation achieved by cyclic movement of an annular Li20 test assembly relative to a stationary point source was a step forward in better simulation of the energy and angular distributions of the incident neutron source found in Tokamak plasmas. Thus...

one of known methods for measuring, forecasting and managing risk is value at risk, which recently has been used by financial institutions extensively. value at risk (var) is a method for recognizing and evaluating risk and uses standard statistical techniques that have daily using in other contexts. this research is seeking a career for managing investment risk in stock exchange and selection ...

This work presents an extensive study on Monte Carlo radiation transport simulation and thermoluminescent (TL) dosimetry for characterising mixed radiation fields (neutrons and photons) occurring in nuclear reactors. The feasibility of these methods is investigated for radiation fields at various locations of the Portuguese Research Reactor (RPI). The performance of the approaches developed in ...

This paper demonstrates the applicability of Monte Carlo analysis to perform nuclear reactor core simulations with thermofluid feedback from a computational fluid dynamics code. An interface program, McSTAR, was written to couple MCNP5 to the commercial computational fluid dynamics code STAR-CD. McStar is a Perl script which alternately executes MCNP5, STAR-CD and cross section update routines ...

 Introduction: Monte Carlo method is often applied in radiation therapy as utilized in all the branches of science. An important requirement for successful radiotherapy is carefully examine the dose distribution specifications and decrease the difference between these features with experience to an acceptable level. In this study, the characteristics of 6, 15 and 20 MeV incident x-rays are prov...

in this study, monte carlo statistical mechanical simulations for vinblastine and vincristine werecarried out in standard manner using the metropolis sampling technique in canonical (t, v, n)ensemble., geometrical optimizations of vinblastine and vincristine were carried out with the hfmethod coupled to 6-31g(d) basis sets for all atoms. simulation was done by four force fields ofmm+, bio+, amb...

an important need in radiation therapy is a fast and accurate treatment planning system. this system using ct data and characteristics of the radiation beam, calculates the dose in all points of the patient’s volume. two main factors in planning system are “accuracy” and “speed”. according to these factors, various generation of treatment planning systems are developed.   this article is the re...