Environment maps are a popular method of reproducing complex natural lighting. However, current methods for hardware environment map shadows depend on significant pre-computation and cannot support dynamic objects. This work presents a pre-process that decomposes an environment map into two components: a set of area lights and an ambient map. Once the map is split into these components, each is...

background: field matching problems in abutting electron fields can be managed by using spoilers. objective: the aim of this study was to design a monte carlo framework for the assessment of spoiler application in abutting electron fields. methods: a siemens primus treatment head was simulated for a 5 mev electron beam using beamnrc and dosxyznrc, egsnrc user codes. validation of beam model was...

Time is a fundamental factor during stroke treat-ments. A fast, automatic approach that segmentsthe ischemic regions helps treatment decisions. In clinical use today, set of color-coded parametric maps generated from computed tomography per-fusion (CTP) images are investigated manually to decide plan. We propose an method based on neural network using segment the two (core and penumbra) in pati...

See related article, pages 1638–1643. In the past decade there has been considerable scientific discussion about the metabolic state of the tissue surrounding a brain hemorrhage. The scientific discussion has focused mostly on the question of whether brain ischemia is present in this “penumbral tissue,” which has great clinical relevance because the presence of ischemia would drive clinical tre...

PURPOSE To determine the cause of negative dysphotopsia and the location, appearance, and relative intensity of such images in pseudophakic eyes. SETTING Baylor College of Medicine, Houston, Texas, USA. DESIGN Reporting available data addressing a specific clinical question. METHODS Negative dysphotopsia was simulated using the Zemax optical design program. The nominal values for the pseu...