dust storms are destructive climate phenomenon which damage farm, installations,roads,traffic and etc indemnifiable. this phenomena at dry and pertaining regions of the country as environmental perils, is effected by particular atmospheric condition.if the origin and extention of this phenomenon be recognized the damages can be decreased or counteracted.the studied about dust storm show thirtee...

The recent integration of the internet with geo-information systems (GIS) has evolved the concept of Internet Distributed GeoInformation Services. Numerous research and implementation studies of standards of metadata, geo-libraries, data storage and retrieval etc. are being done giving way to exchange and share of geo-information. However, very little effort has gone into making it possible to ...

height is amongst the most delicate subjects of geodesy. thanks to the global navigation satellite systems (gnss) like gps or glonass, 3d point positioning of points, by geometrical positioning, since years ago has become a common practice. the height derived from these ways has a geometrical concept. in civil projects the physical concept of the height is more demanded. orthometric height, , i...

A consistent reference system for height determination at the national scale supports economic activity and is an essential component of the basic infrastructure that enables good governance of our natural resources. Accessed by stakeholders in the field of surveying, engineering, mapping and earth sciences, the height reference system maintains compatibility among all types of geo-referenced i...

in many countries, leveling networks are established for height determination which is one of the most important topics in geodesy. in these networks, the sum of the leveled height differences between a and b will not be equal to the difference in the orthometric heights ha and hb. the reason is that the leveling increment ?n, as we henceforth denote it, is different from the corresponding incr...

If images acquired fromUnmanned Aerial Vehicles (UAVs) need to be accurately geo-referenced, the method of choice is classical aerotriangulation, since on-board sensors are usually not accurate enough for direct geo-referencing. For several different applications it has recently been proposed to mount thermal cameras on UAVs. Compared to optical images, thermal ones pose a number of challenges,...

Recently ontology research has received much attention in geo-information science and the concept of ontology is very important for spatial information concept modeling and data sharing, classification of geographical classes. More importantly, it enriches the semantic theory of spatial information. Geo-information services and geo-information interpretation and extraction are the two main appl...