This paper describes a unified framework for the problems of modelling and processing geographical entities. We propose a general definition of geographical objects, and show that the different types of geographical data can be expressed as particular cases of this definition. Furthermore, we present a taxonomy for the various types of GIS operations, defined in terms of the properties of this ...

This paper deals with the issue of watermarking 2D-vector data which are used in Geographical Information Systems (GIS). The watermark is embedded in the tolerance range of the coordinates, where one bit of the watermarking information is represented by one PN-sequence, whose elements consist of the two values “+tolerance” and “– tolerance”. To robustly embed one bit of the watermarking informa...

In recent years, forest fires frequency and intensity has increased, causing a new awareness about their impact not only on vegetation, but also on hydrological regime. Changes in vegetation influence the processes of interception and evapotranspiration, seriously affecting the hydrological cycle. Forest fires can also affect hydrological processes indirectly, altering the hydraulic properties ...

Drawing is a simple, common, and expressive way to represent concepts and relationships for geographical databases. However, the possibility to revise the sketch and multiple interpretations of different shapes and their relationships in the sketch makes very difficult to determine the correct interpretation of the user goals. This paper starts from the assumption that the sketched picture is g...

Issues in the area of geographic databases, caused by the lack of a standard geographic conceptual data model, can be classified as interoperability problems. This paper proposes a method to reach horizontal interoperability, i.e., a schema can be transformed in another schema designed using a different model. UML infrastructure and the Enterprise Architect CASE tool are used in the process. To...

Aim When precise coordinate data for training species distribution models (SDMs) are lacking, climatic variables are often assigned to centroids of geopolitically defined regions, frequently counties. This is problematic because approximations using centroids may not be representative of the regional climate or the locality from where species actually occur, thus leading to spurious conclusions...

To be able to utilise geographical data for analysis, one should know something about the quality of the data. In present geographical data standardisation proposals (SDTS, CEN TC287), several aspects of geographical data quality have been described, such as lineage (data collection and processing history), spatial accuracy, attribute accuracy, completeness, logical consistency and currency. Me...

We study how cultural distance affects the rejection of imposed institutions. To this purpose, we exploit the transplantation of Piedmontese institutions on Southern Italy which occurred during the Italian unification. We assemble a novel and unique dataset containing information on episodes of brigandage, a form of violent uprising against the unitary government, at the municipal level. We use...

It is important to understand urban auto markets from a spatial perspective. Specifically, the question of how to simplify and visualize the relatedness of the complicated urban markets arises. Based on the concept of ‘product space’, this research explores the similarity between Chinese cities and identifies the city clusters using data of automobile sales in 2012. A city’s automobile market i...