In this paper, we consider a discrete-time queue of Geo/Geo/c type with geometric repeated attempts. It is known that its continuous counterpart, namely the M/M/c queue with exponential retrials, is analytically intractable due to the spatial heterogeneity of the underlying Markov chain, caused from the retrial feature. In discrete-time, the occurrence of multiple events at each slot increases ...

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...

Since the Digne Convention in 1991, literature related to Geoparks has gained a growing interest on academy’s part, especially achieving preservation of geological sites through sustainable tourism. This article aims provide an analysis academic research Geoparks, based publications Scopus database period 2002–2020. Bibliometric methods and bibliographic display maps were examined using VOSview...

A practical hierarchical component-based WebGIS model referred to as Geo-Union is presented. Geo-Union consists of four layers: storage layer, service layer, component layer and application layer. Service layer is partitioned into another two layers: Geo-Union client and Geo-Union server. The architectures and object diagram of each layer in Geo-Union are discussed in details. After that, four ...

An argumentation map is an online discussion forum for spatially related topics that combines the forum with an interactive map. The utility of an argumentation mapping tool highly depends on the accuracy and quantity of the geo-tags that link the discussion contributions to geographic locations. These geo-tags can be created manually by the users of the argumentation map or automatically by a ...