The ballast of the railway track is constantly changing due to dynamic forces of train traffic that results in the crushing of the rocks. The feasibility to simulate each particle makes the discrete element method (DEM) suitable for the task. Different DEM particle models are introduced in our paper and the adequate one was chosen. This new method is based on crushable convex polyhedral element...

In this paper we discuss about the need of a new DEM representation for simulation in GIS. This leads us to analyse through quality criteria the current DEM structures. Then we propose a new DEM representation adapted for spatial and graph terrain analysis. An algorithm is presented and the qualities of this structure are analysed. Finally, this structure is used in a thematic application for a...

Recently software libraries known as physics engines have begun to gain interest within the computing communities. They are designed primarily for use within the computer game industry but also currently find credence within real-time animation and robotics simulation. The technical requirements of a Discrete Element Model (DEM) are markedly similar to that of a gaming rigid body problem. A DEM...

Within Computer Science, reusability of specific modular software components is generally accepted as best practice. Simulation techniques such as Discrete Element Modelling (DEM) rely on the well defined problems of Newtonian physics, and while differences exist in the methods defined to compute solutions to these problems, each method follows the same basic set of premises. Recently, librarie...

Partial randomization dynamic element matching (DEM) was recently introduced as a promising DEM technique for low harmonic distortion digital-to-analog conversion. The DEM technique is well suited for applications such as direct digital synthesis in wireless communication systems for which low hardware complexity is essential in addition to low harmonic distortion. Previously reported simulatio...

Dynamic Compaction (DC) is a common deep compaction method that is usually used for densification of coarse-grained soils. Although traditional continuum-based models such as the Finite Element Method can be successfully applied for assessment of stress distributions or deformations induced by DC, they are typically not adequate for capturing the grain scale mechanisms of soil behavior under im...