discrete element method (dem) is extensively used for mathematical modeling and simulating the behavior of discrete discs and discrete spheres in two and three dimensional space, respectively. prediction of particles flow regime, power draw and kinetic energy for a laboratory or an industrial mill is possible by dem simulation. in this article, a new approach was used to assess the main paramet...

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...

The discrete element method (DEM) has been used as a popular simulation method in order to verify the designs by visualizing how materials flow through complex equipment geometries.  Although DEM simulation is a powerful design tool, finding a DEM model that includes all real material properties is not computationally feasible.  In order to obtain more realistic results, particle energy loss du...

In calibration of model parameters for discrete element method (DEM) based models the focus lies on matching mean key performance indicator (KPI) values from laboratory experiments to those simulation results. However, due stochastic nature granular processes experimental results can show large variances. To include behaviour, interpolation-based and regression-based metamodels are trained with...

One of the main challenges in using the Discrete Element Method (DEM) is to specify the correct input parameter values. In general, the models are sensitive to the input parameter values and accurate results can only be achieved if the correct values are specified. For the linear contact model, micro-parameters such as the particle density, stiffness, coefficient of friction, as well as the par...

The main product of the TanDEM-X mission is a global interferometric digital elevation model (DEM) that is finally calibrated due to residual systematic offsets and tilts. For the final DEM product single acquisitions (socalled data takes) are calibrated and merged to tiles of a size of 1°x1°. Finally the globe will mostly be covered with two acquisitions. The quality of the calibration of the ...

TanDEM-X is the first bistatic space borne SAR mission [1]. It is formed by adding a second, almost identical spacecraft to TerraSAR-X and flying them in a closely controlled formation with typical distances between 250 m and 500 m. The primary goal of the mission is the derivation of a high-precision global Digital Elevation Model (DEM) according to HRTI level 3 quality [2]. To achieve this ac...

The TanDEM-X mission will derive a global digital elevation model (DEM) with satellite SAR interferometry. Two radar satellites (TerraSAR-X and TanDEM-X) will map the Earth in a resolution and accuracy with an absolute height error of 10m and a relative height error of 2m for 90% of the data. In order to fulfill the height requirements in general two global coverages are acquired and processed....