When performing a regional-scale geomorphometric analysis, one might face a decision on whether to derive morphometric data from a low-resolution DEM or to calculate basic derivatives from a higher resolution dataset and average these data afterwards. This paper investigates differences between morphometric parameters (slope and aspect) derived from a resampled DEM and resampled morphometric da...

considerations on the explosion resistant design of special infrastructures have increased in the recent years. amongst the various types of infrastructures, road and railway tunnels have a unique importance due to their vital role in connection routes in emergency conditions. in this study, the explosion effects of a projectile impacting on a railway tunnel located in a jointed rock medium has...

The HRS (high resolution stereo) is an autonomous imaging system on SPOT 5. It has been designed especially for the generation of digital elevation models (DEMs). The combination of a forward and a backward view do allow a stereoscopic imaging with a height to base relation of 1.2 and just 90 seconds time interval. Some images, which are usually not accessible and used only by SPOT Image for th...

Das alte Bibliotheks-PC-Netz mit ca. 300 Rechnern war 1995 nach dem klassischen Netzwerk-Computing-Modell entstanden, bei dem alle benötigten Anwendungen auf dem Desktop eines voll ausgestatteten PCs ausgeführt wurden. Das Netz (TCP/IP) verband dann diese Rechner untereinander und ermöglichte weitere übergeordnete Anwendungen (Sicherungen, Mail, Internet etc.). Als Betriebssystem wurde damals b...

In a Cryptographic primordial, the functions of the digital signature and the public key encryption are concurrently carried out. To safely communicate incredibly large messages, the cryptographic primordial known as the signcryption is effectively employed. Though a lion’s share of the public key based mechanism are appropriate for miniature messages, the hybrid encryption (KEM-DEM) offers a p...

With the aim of probing for design theory of cutterhead excavation system of earth pressure balance (EPB) machine, the parameters representing the system performance are concluded firstly. Then a 3D model for cutterhead excavation system of EPB machine is presented with the discrete element method (DEM) software PFC, which is capable of simulating the tunneling ground in site, the machine struc...

This paper describes the architecture of high performance, particle simulation machine, DEM-1 for short-range particle interaction computations. All existing particle simulation machines have specialized pipelines to calculate long-range particle interactions effectively. However, their ability to perform particle simulations efficiently diminishes with short-range interactions. The communicati...

In this work, a numerical study of the gas-solids flow in a 3D gas-fluidized bed with an immersed horizontal cylinder is performed using the combined computational fluid dynamics (CFD) and discrete element method (DEM). In order to investigate the wall effect, a sensitivity study of bed thickness is performed first to obtain the critical bed thickness at which the bed can be regarded as 3D. The...

With the launch of the recent high-resolution Synthetic Aperture Radar (SAR) satellite missions, e.g., TerraSAR-X, RadarSAT-2, and CosmoSkymed, the technique of radargrammetry motivates interest again to potentially improve upon the level of detail and accuracy of Digital Elevation Models (DEM) from a global coverage perspective as an alternative to data derived from Interferometric SAR (IFSAR)...

Resolution of a multibit delta-sigma modulator (DSM) is limited by its internal digital-to-analog converter (DAC) nonlinearity that is usually caused by circuit mismatch errors while realizing. Recently, some dynamic element matching (DEM) methods were proposed for reducing mismatch errors. Two main difficulties of different dynamic element matching (DEM) techniques relate to instability and co...