We describe a scheme for implementing dynamic casts suitable for systems where the performance and predictability of performance is essential. A dynamic cast from a base class to a derived class in an objectoriented language can be performed quickly by having the linker assign an integer type ID to each class. A simple integer arithmetic operation verifies whether the cast is legal at run time....

We present a novel algorithm for rendering physically-based soft shadows in complex scenes. Instead of casting shadow rays, we place both the points to be shaded and the samples of an area light source into separate hierarchies, and compute hierarchically the shadows caused by each occluding triangle. This yields an efficient algorithm with memory requirements independent of the complexity of t...

The results of a computational study of feeding and the promotion of feeding by yield improvement techniques is presented. The computer simulations were performed using a commercial solidification software package examining the simple plate-like geometries addressed in the SFSA feeding rules. Solidification criteria from the computer model were used to develop simulation determined feeding dist...

Determining alloy shrinkage factors is very important for the investment casting process. Casting dimensions can be obtained from numerical simulations of heat transfer and deformation phenomena. The accuracy of the dimensional results depends on heat transfer results. In order to validate heat transfer models, temperature data were obtained during casting of aluminum alloy A356 in shell molds ...

The problem motivating the current work is a mould filling during casting process. The aim of our analysis is to provide a simple experimental model simulating the main flow characteristics accompanying such process. Hence, the hot fluid is supplied under high pressure into an inclined box. Fluid flows inside the box between two cold isothermal walls, passing obstacles simulating internal compl...

Numerical programs usually include type-casting instructions which convert data among different types. Identifying unsafe type-casting is important for preventing undefined program behaviors which cause serious problems such as security vulnerabilities and result non-reproducibility. While many tools had been proposed for handling sequential programs, to our best knowledge, there isn’t a tool g...

Ceramo-metal dental casting alloys are used for crowns and fixed partial dentures (bridges). Ni-Cr and Co-Cr are base ceramo-metal dental casting alloys and now account for the majority of the fixed metalceramic restorations used clinically. The corrosion of these alloys result in release of elemental components with potential adverse biological reactions. It is of great importance to investiga...

This paper presents a novel method to accelerate volume ray casting as used in virtual colonoscopy. The method exploits a pre-processing visibility technique to identify the potentially visible portions of the colon. Then it applies a space leaping technique based on the projection of the visible boundary voxels of the colon onto the image plane. The method has been tested using a synthetic dat...