Air pollution has received considerable attention by local and global communities (Wald et al, 1999). Many major cities have established air quality monitoring stations but these stations tend to be scarcely distributed and do not provide sufficient tools for mapping atmospheric pollution since air quality is highly variable (Wald et al, 1999). Satellite remote sensing is a valuable tool for as...

Introduction. The application of geographic information system (GIS) technologies is a promising technology for mapping and evaluating landslide hazards. At present, satellite-based terrestrial sensing widely used. Satellite images make it possible not only to identify individual landslides, particularly in hard-to-reach areas, but also those locations where processes have manifested, are manif...

The coastal region of Chabahar Gulf with 1113.7km2 area has been located in the southeast of Iran. In this research, satellite images of ETM+ (2004) were used in order to zoning of sedimentary environments in this Gulf. Methodology of this research was baesd on synthesis of supervised and unsupervised classifications in GIS and ENVI softwares. Based on studies and calculat...

BACKGROUND: Household-level geographic information systems (GIS) database are usually constructed using the geographic positioning system (GPS). In some research settings, GPS receivers may fail to capture accurate readings due to structural barriers such as tall buildings. We faced this problem when constructing a household GIS database for research sites in Karachi, Pakistan because the sites...

A wide range of data collected by monitoring systems and by mathematical and physical modelling can be managed in the frame of spatial models developed in GIS. In addition to data management and standard environmental analysis of air pollution, data from remote sensing (aerial and satellite images) can ehance all data sets. In spite of the fact that simulation of air pollutant distribution is c...

forest classification on the basis of satellite images is a promising technique both for primary map production and for map updating and forest monitoring. for accurate for-est classification into three classes, using mapping by canopy cover density “high spatial resolution satellite images have to be used in order to obtain the required spatial detail” [schneider, 1999]. at the same time, the ...

as the information carried in a high spatial resolution image is not represented by single pixels but by meaningful image objects, which include the association of multiple pixels and their mutual relations, the object based method has become one of the most commonly used strategies for the processing of high resolution imagery. this processing comprises two fundamental and critical steps towar...

geological studies are basic formof operations for the exploration and development of oil and gas fields.preparation of topographical and geological maps and drawingcross section from thesemaps formspart of these operations. existing lineaments in the study area are important, and should be considered in drawing the geological sections. the evaluation of wells stability is one of the important ...