The ASTER DEM generation for geomorphometric analysis of the Central Alborz mountains, Iran

This research focuses on the ASTER DEM generation for visual and mathematical analysis of topography, landscapes and landforms, as well as modeling of surface processes of Central Alborz, Iran. ASTER DEM 15 m generated using tie points over the Central Alborz and Damavand volcano with 5671 m height from ASTER (Advanced Space borne Thermal Emission and Reflection Radiometer) satellite data using PCI Geomatica 9.1. Geomorphic parameters are useful to identify and describe geomorphologic forms and processes, which were extracted from ASTER DEM in GIS environment such as elevation, aspect, slope angle, vertical curvature, and tangential curvature. Although the elevation values are slightly low in altitudes above 5500 m asl., the ASTER DEM is useful in interpretation of the macro- and meso-relief, and provides the opportunity for mapping especially at medium scales (1:100,000 and 1:50,000). ASTER DEM has potential to be a best tool to study 3D model for to geomorphologic mapping and processes of glacial and per glacial forms above 4300 m asl

Landslides and active faults using remote sensing and GIS techniques in Central Alborz mountains, Iran

The attempt has been done on study of habitat factors for the distribution of 370 landsides. This study is based on landform features and landslides associated with active faults distribution using remote sensing, GIS and GPS techniques in the Central Alborz, North Iran. Field observations show that the mass movements on low angle occur most frequently near to active faults. In steep slopes avalanche and planar slides are dominant. In this study digital image processing has been done on the ASTER L1A, L1B and Landsat7 ETM+ images. GIS layers have been extracted from 370 historical landslides and active faults over the study area. Digital Elevation Model (DEM) (15m) has been generated from ASTER stereo pair data using PCI Geomatica 9.1 software. The use of a (15m) DEM is a potential substitute in tectonic activity analysis, as it highly correlates with slope instability, geomorphologic processes and factors affecting landslides. Appropriate landform parameters have been derived which are indicating landslides and faults distribution, exposure towards rain and snow. Tectonic classification schemes decomposing the landscape into basic landform-elements proved useful for characterizing a zonal, altitudinal landslide classes. The results show that more than 72 percent of landslide points are situated on the active faults buffer zone. It can be used as fundamental data for hazard prediction, land use planning and construction in study area

A novel ontological approach to modelling engineering processes: A coupled tank system case study

Many modelling techniques such as Artificial Neural Network (ANN) and SIMULINK have been employed in engineering processes such as control systems. However, these techniques lack some beneficial features such as the auto-classification and self-awareness of knowledge, the dynamic knowledge discovery, validating the consistency of knowledge and the possibilities of embedding Semantic Web Rule Language (SWRL) rules into various modelling tasks. This paper presents an original and innovative ontology design that models the coupled tanks system (CTS) with additional capabilities of providing aforementioned advantages. This new approach for modelling engineering phenomena employs the Web Ontology Language (OWL) and also processes the capabilities of incorporating Description Logics (DL) and Semantic Web technologies into the ontology-based design. The results obtained in this paper show the successful demonstration and implementation of our new knowledge modelling approach

Application of Geographic Information System in seismic hazard assessment for the Central Alborz, Iran

The assessment of the seismic hazard of the Central Alborz in Northern Iran, expressed in terms of strong ground-motion which is demonstrated using Geographical Information System (GIS) techniques. The inability of a single hazard study to meet the needs of users and to handle the uncertainties of such analyses, demands a more user friendly procedure. GIS technology provides facilities for seismic hazard assessment which permits users to see the geographical distribution of calculated effects from different viewpoints. GIS is a powerful tool which is potentially very useful in seismic hazard analysis, seismic risk assessment and seismic zonation studies. This study applied GIS and spatial modeling using different data sets such as Digital elevation models (DEM), topographic maps, century earthquake data, and geological maps to help establish the seismic hazard assessment and analyze the tectonic history of the Alborz area. A period of historic seismicity encompassing more than 2,000 years has been collected and used as the earthquake catalogue data for this study. GIS programs are used in this research to collect, manipulate, generate and analyze various data input to seismic hazard analysis. GIS based methodology is introduced to combine available information on seismicity, tectonics and strong ground-motion. The external computer programs applied in this work are linked to the GIS, adding flexibility and analytical capabilities to the seismic hazard procedure. The traditional probabilistic approach is modified to account for detailed regional variation of seismicity parameters. Seismic hazard computer program is examined whether it is able to perform hazard analysis interactively within the GIS environment to yield acceptable results. The methodology is flexible as regards the way input data for seismic source boundaries, regional focal depth, faulting orientation, and seismogenic parameters are implemented. The procedure is capable of handling further potential site-dependent and site-specific hazard analysis. In the proposed approach, GIS raster –based data models are used in order to model geographical features in a cell-based system. The cell- based source model proposed in this study provides a framework for implementing many geographically referenced seismotectonic factors in to seismic hazard modeling. Using GIS methods in this study, seismic source zones are delineated based on the relationship of the observed earthquakes with the tectonic manifestations of the geological units. Maps with seismic interpretation are produced as a tool to delineate seismic source areas, to study the completeness of the earthquake catalogue, to determine the seismic activity, and to define recurrence parameters for the source areas. Various maps representing different aspects of seismic hazard are calculated and presented in this study. Probabilistic seismic Intensity maps and probabilistic ground acceleration maps are calculated based on different assumptions regarding seismicity parameters, source to- site distance, and alternative seismic source zones. Subsequently, the uniform hazard spectra are calculated in some major cities of Central Alborz, and the effects of uncertainties in the calculated ground motion are studied