Helical tomotherapy presented many unique dosimetric challenges and solutions during the initial commissioning process, and some of them are presented. The dose calculation algorithm is convolution/superposition based. This requires that the energy fluence spectrum and magnitude be quantified. The methodology for doing so is described. Aspects of the energy fluence characterization that are uni...

Diamond photoconductive detectors have previously been shown to be suitable for detection of deep ultraviolet nanosecond-scale pulses from excimer lasers, which are to be used in next generation lithographic systems. Using simple test circuitry and low bias voltages easily measurable responses were observed when these detectors were illuminated with laser pulses at typical laser fluence levels....

Profiling of particle beams is one the most important diagnostic procedures for operating any kind accelerator. In this work, proton beam profilers, based on fluence measurements performed by recording changes carrier lifetime in Si material and scintillation intensity thin GaN layers, caused radiation induced defects emission centres, are presented. The penetrative (26 GeV/c) stopped (1.6 MeV)...

Although many methods exist for intensity modulated radiotherapy (IMRT) fluence map optimization for crisp data, based on clinical practice, some of the involved parameters are fuzzy. In this paper, the best fluence maps for an IMRT procedure were identifed as a solution of an optimization problem with a quadratic objective function, where the prescribed target dose vector was fuzzy. First, a d...

fluence of internal or external factors in driving wildfire management.

We have studied the influence of the end of range defects in silicon created by high energy protons and helium ions on subsequent porous silicon formation. The defect generation rate at the end of range is typically ten times higher than that close to the silicon surface. For low fluence irradiation, only the end-of-range region contains enough defects to prevent anodization whereas the low-def...

This study experimentally demonstrated a feed-forward inversion control scheme for maintaining an optimum incident irradiance on photobioreactors (PBRs) during batch cultivation. A data-based modelfree optimization using quadratic fit was utilized to rapidly estimate the optimum average fluence rate set point value that rendered maximum microalgae growth rate. Then, the feed-forward inversion c...

The new SuperLHC upgrade will impose severe restrictions on the radiation hardness of silicon detectors since a maximum fluence of 10 particles/cm is foreseen in the innermost region. Microstrip detectors have been fabricated in p-type high resistivity float zone silicon at CNM facilities, been irradiated at the TRIGA reactor in Ljubljana to a fluence of 10 neutrons/cm and characterized at IFIC...

A surprisingly large concentration of radioactive Be was observed in the upper atmosphere at altitudes above 320 km on the LDEF satellite that was recovered in January 1990. We report on follow-up experiments on Russian spacecraft at altitudes of 167 to 370 km during the period of 1996 to 1999, specifically designed to measure Be concentrations in low earth orbit. Our data show a significant co...