INTRODUCTION In pebble bed reactors (PBRs), fuel pebbles containing TRISO particles continuously circulate within the core during operation, while the coolant fluid, either helium gas (in Pebble Bed Gas-cooled Reactors) or molten flibe salt (in Pebble Bed-Advanced High Temperature Reactors), continuously passes through the pebbles to transfer the heat generated by fission reactions out of the c...

for designing tillage implements it would be better to estimate soil forces exerted to the implements. many researches showed that numerical method of discrete element method (dem) is the cheapest and fastest technique for modeling granular material such as soil and especially sandy soil. in this study, paraplow and bentleg tines performance was compared with conventional tine using experimenta...

One limitation of Computational Fluid Dynamics based investigations of industrial scale particle flow phenomena is the inability to properly describe the effects of particle-particle interactions. Discrete element methods (DEM) present an opportunity to study such interactions. In flows with higher solids loadings these particle-particle interactions give rise to microstructure formation. Signi...

Mit dem Waldmanagementsystem „Virtueller Wald“1 (www.virtuellerwald.net) gehen die sprichwörtlichen Zeiten, in denen man den Wald vor lauter Bäumen nicht sehen konnte, dem Ende entgegen. Grundlage hierfür ist eine flächendeckende, qualitativ hochwertige, aktuelle, auswertbare georeferenzierte Waldinventur, die mit Unterstützung leistungsfähiger Sensordaten verarbeitender Algorithmen auf der Bas...

This paper presents the singularity-free dynamic equations of the dynamically equivalent manipulator (DEM) of spacecraft-manipulator systems. The DEM is a fixed-base manipulator with the same dynamic properties as the corresponding free-floating spacecraftmanipulator system. The DEM consists of a spherical joint, representing the spacecraft and a robotic arm with the same joint types as the spa...

One challenge of todays research is the realistic simulation of granular materials, like sand or powders, consisting of millions of particles. In this article, the discrete element method (DEM), as based on molecular dynamics methods, is introduced. Contact models are at the physical basis of DEM. A set of the most basic force models is presented involving either elasto-plasticity, adhesion, vi...

A multibit analog-to-digital converter can achieve high resolution with a lower order modulator and lower oversampling ratio than a single-bit design. However, in a multibit modulator, quantization level errors in the internal multibit quantizer can limit the modulator’s signal-to-noise-and-distortion and spurious-free dynamic range. For a CMOS analog-to-digital converter using a flash analog-t...

Rheological properties of pitch and pitch/coke mixtures at temperatures around 150 °C are of great interest for the carbon anode manufacturing process in the aluminum industry. In the present work, a cohesive viscoelastic contact model based on Burger's model is developed using the discrete element method (DEM) on the YADE, the open-source DEM software. A dynamic shear rheometer (DSR) is used t...

Handling and processing of bulk granular materials is of major importance in many industries including agriculture, chemical, food, pharmaceutical, construction and mining. In recent decades, the Discrete Element Method (DEM) is increasingly adopted for studying the complex behaviour of granular materials and simulating the industrial processes in many applications. DEM computes at individual p...

Es werden Themenschwerpunkte der gegenwärtigen Modernisierungsdebatte zum Datenschutzrecht dargestellt, mit denen sowohl auf die Entwicklung der Datenverarbeitungstechnik als auch auf den gestiegenen wirtschaftlichen Wert von Informationen reagiert werden soll. Grundlage ist ein Gutachten zur Modernisierung des Datenschutzrechts, das im Jahr 2001 im Auftrag des Bundesministeriums des Innern ers...