Although ray tracing based propagation prediction models are popular for indoor radio wave propagation characterization, most of them do not provide an integrated approach for achieving the goal of optimum coverage, which is a key part in designing wireless network. In this paper, an accelerated technique of three-dimensional ray tracing is presented, where rough surface scattering is included ...

Ray-primitive intersection tests are the most important operations in ray tracing. The ray-box culling algorithm was presented to accelerate these intersection tests on grid structures, but this algorithm has not been widely used due to the poor ray traversal performance of the grid structures themselves. In this paper, we demonstrate how to apply this algorithm to tree structures and investiga...

We proposed a new public-key traitor tracing scheme with revocation capability using the dynamic share and entity revocation techniques. The enabling block of our scheme is independent of the number of subscribers, but dependent on the collusion and revocation thresholds. Each receiver holds one decryption key only. Our traitor tracing algorithm works in a black-box way and is conceptually simp...

Knowledge of the worm origin is necessary to forensic analysis, and knowledge of the initial causal flows supports diagnosis of how network defenses were breached. Fast and accurate online tracing network worm during its propagation, help to detect worm origin and the earliest infected nodes, and is essential for large-scale worm containment. This paper introduces the Accumulation Algorithm whi...

The biggest challenge for geometrical room acoustic computer models is to capture complex wave phenomena while maintaining the low computational load of the ray tracing algorithm. Special corrections must be added to the ray tracing algorithm to account for wave phenomena such as edge diffraction, which are ignored by classical geometrical acoustics. ODEON, a well-known geometrical computer mod...

We propose a principal curve tracing algorithm that uses the gradient and the Hessian of a given density estimate. Curve definition requires the local smoothness of data density and is based on the concept of subspace local maxima. Tracing of the curve is handled through the leading eigenvector where fixed-step updates are used. We also propose an image segmentation algorithm based on the origi...

A dynamic task allocation algorithm for ray-tracing by progressive refinement on a distributed-memory parallel computer is described. Parallelization of progressive ray-tracing is difficult because of the inherent sequential nature of the sample location generation process, which is optimized (and different) for any given image. We report on experimental results obtained from our implementation...

We propose a principal curve tracing algorithm that uses the gradient and the Hessian of a given density estimate. Curve definition requires the local smoothness of data density and is based on the concept of subspace local maxima. Tracing of the curve is handled through the leading eigenvector where fixed-step updates are used. We also propose an image segmentation algorithm based on the origi...

In this paper, we analize the existing algorithms for tracing straight lines and planes in voxel space. A new fast algorithm for tracing a plane is presented. The new algorithm is based on a striping technique, and is noticeably faster than existing algorithms. This comes at the expense of some precision. The algorithm has been implemented in a software environment called ELISA built to help in...

We propose a GA ray-tracing method which applies a genetic algorithm to ray tracing in order to complete the large-scale computation of estimating radio propagation in a practical amount of time. We describe the GA ray-tracing method as well as a demonstration of its effectiveness through numerical simulation .