Here light propagation and radiation transfer of ultrafast laser pulses in heterogeneous biological tissues are simulated by use of the discrete-ordinates method (DOM). Formulations for solving the time-dependent radiation-transfer equation are deduced for three-dimensional geometries incorporating the Fresnel specularly reflecting boundary condition and characteristics of ultrafast laser pulse...

This study analyzes the thermal performance of solar thermal energy using double-pass absorber plate in Sanandaj, Iran. To this end, a mathematical model was encoded according to the energy and exergy balance equations and solved by MATLAB software. Given the environmental conditions and radiation intensity of a winter day in Sanandaj, the effects of external parameters such as radiation intens...

background: finding a suitable method for rapid, accurate and reliable estimation of absorbed dose has high priority in management of the radiation exposed persons. shortly after radiation exposure, apoptosis is a major detriment in proliferative tissues such as the hematopoietic system. therefore, quantification of apoptosis in these tissues could be useful for rapid estimation of radiation ex...

Background: Ultraviolet (UV) radiation is divided into three regions: UVA, UVB, and UVC. Both the quality and quantity of solar UV radiation vary with various factors including the elevation of the sun above the horizon, as well as absorption and scattering of UV photons by molecules in the atmosphere, notably ozone and clouds. It is clear that whereas a moderate amount of UV exposure ...

Multileaf collimators (MLCs) are the prevailing tool for the realization of radiation fields in intensity modulated radiation therapy (IMRT). One step in the treatment planning is to determine a set of leaf positions realizing a certain intensity modulated radiation field. In this paper we suggest two extensions in the use of the MLC that lead to considerable savings in terms of monitor units, ...

The aim of this paper is to study the fine structure of the Cherenkov rings. We analyze the experiments performed by one of authors (Zrelov) in which no special focusing devices were used. The broad Cherenkov ring was observed in the plane perpendicular to the motion axis. Using the exact and approximate formulas we investigate how a charge moving uniformly in a medium radiates in a finite spac...