methods retrospective cohort study of blunt trauma patients with rib fractures at a level i trauma center that had both a cxr and a ct chest. the ct finding of ≥ 3 additional fractures in patients with ≤ 3 rib fractures on cxr was considered clinically meaningful. student’s t-test and chi-square analysis were used for comparison. results we identified 499 patients with rib fractures: 93 (18.6%)...

We propose a new algorithm to compute the X-ray transform of an image represented by unit (pixel/voxel) basis functions. The fundamental task is equivalently calculating intersection lengths ray with associated units. For given ray, we derive sufficient and necessary condition for non-vanishing intersectability. By this condition, can distinguish units that produce valid intersections ray. Only...

Many scientiic applications that run on today's multiprocessors, such as weather forecasting and seismic analysis, are bottlenecked by their le-I/O needs. Even if the multiprocessor is conngured with suucient I/O hardware, the le-systemsoftware often fails to provide the available bandwidth to the application. Although libraries and enhanced le-system interfaces can make a signiicant improvemen...

In computer graphics, ray tracing has become a powerful tool for generating realistically looking images. Even though ray tracing offers high flexibility, a logarithmic scalability in scene complexity, and is known to be efficiently parallelizable, its demand for compute power has in the past lead to its limitation to high-quality off-line rendering. This thesis focuses on the question of how r...

Interactive ray tracing has seen enormous progress in recent years. However, advanced rendering techniques requiring many million rays per second are still not feasible at interactive speed, and are only possible by means of highly parallel ray tracing. When using compute clusters, good load balancing is crucial in order to fully exploit the available computational power, and to not suffer from...