Background: New technologies for terrain reconstruction have increased the availability of topographic data at a broad range of resolutions and spatial extents. The existing digital elevation models (DEMs) can now be updated at a low cost in selected study areas with newer, often higher resolution data using unmanned aerial systems (UAS) or terrestrial sensors. However, differences in spatial c...

The concept and the computation of terrain representation error (ETR) are investigated and total DEM error is presented as an accuracy index for DEM evaluation at a global level. A promising method of surface modelling based on the theorem of surfaces (SMTS) has been developed. A numerical test and a real-world example are employed to comparatively analyze the simulation accuracy of SMTS and th...

abstract land surface hydrological models has importance in the determination of soil moisture and temperature, the rate of evapotranspiration, stream flow by emphasis on the land surface physical and dynamic process descriptions. in this research, vic land surface hydrological model has been used for the land surface temperature and stream flow determination. the vic runoff simulation in each ...

High resolution digital elevation models (DEMs) have been used in many applications such as civic planning, military mapping and navigation, natural hazard risk assessment, to name only a few. It has been a long history of using photogrammetry and dense ground surveys to draw the contour lines of the terrain and create the elevation model. Nowadays high precision DEMs with the vertical resoluti...

INTRODUCTION The recently developed Phototest is a simple, easy and very brief (<3 minutes) test with theoretical advantages over available dementia screening tests. Our objective was to evaluate its diagnostic accuracy under routine clinical conditions. MATERIAL AND METHODS A phase II cross-sectional validation study of diagnostic tests was performed in a sample of 308 patients referred to a...

A high-fidelity DEM-CFD model is newly proposed for process intensification of packed bed reactors. The discrete element method (DEM) is employed for simulating random packing under gravity with hundreds of spheres in a cylindrical tube. It is verified that the DEM is capable of constituting a packed bed whose voidage well agrees with the literature according to particle-to-tube diameter ratio....

Der Artikel geht zunächst auf die Bedeutung zellulärer Automaten für die Simulation dynamischer Prozesse ein. Im weiteren wird ein Schwerpunkt auf die Simulation der Lagerung von Massengüttern eingegangen, sogenannten Schüttgütern, für die es aufgrund mangelnder Berechnungsverfahren bis heute keine befriedigende numerische Lösung gibt. Mittels zellulärer Automaten sind hierbei zumindest für gro...

It is essential to construct a high precision digital elevation model (DEM) annually or seasonally in tidal flats to monitor coastal erosion. To monitor active coastal changes using the tidal flat DEM, a vertical accuracy of higher than 20 cm is required. We apply space-borne radar interferometry (InSAR) to the Korean tidal flats to test the feasibility of InSAR in tidal flats. We also investig...

Use of disease simulation models has led to scrutiny of model methods and demand for evidence that models credibly simulate health outcomes. We sought to describe recent obstructive lung disease simulation models and their validation. Medline and EMBASE were used to identify obstructive lung disease simulation models published from January 2000 to June 2006. Publications were reviewed to assess...