Multi-Paradigm Reasoning for Access to Heterogeneous GIS

Accessing and querying geographical data in a uniform way has become easier in recent years. Emerging standards like WFS turn the web into a geospatial web services enabled place. Mediation architectures like VirGIS overcome syntactical and semantical heterogeneity between several distributed sources. On mobile devices, however, this kind of solution is not suitable, due to limitations, mostly regarding bandwidth, computation power, and available storage space. The aim of this paper is to present a solution for providing powerful reasoning mechanisms accessible from mobile applications and involving data from several heterogeneous sources. By adapting contents to time and location, mobile web information systems can not only increase the value and suitability of the service itself, but can substantially reduce the amount of data delivered to users. Because many problems pertain to infrastructures and transportation in general and to way finding in particular, one cornerstone of the architecture is higher level reasoning on graph networks with the Multi-Paradigm Location Language MPLL. A mediation architecture is used as a “graph provider” in order to transfer the load of computation to the best suited component – graph construction and transformation for example being heavy on resources. Reasoning in general can be conducted either near the “source” or near the end user, depending on the specific use case. The concepts underlying the proposal described in this paper are illustrated by a typical and concrete scenario for web applications

A Framework for Semantic Interoperability for Distributed Geospatial Repositories

Interoperable access of geospatial information across disparate geospatial applications has become essential. Geospatial data are highly heterogeneous -- the heterogeneity arises both at the syntactic and semantic levels. Finding and accessing appropriate data in such a distributed environment is an important research issue. The paper proposes a methodology for interoperable access of geospatial information based on Open Geospatial Consortium (OGC) specified standards. An architecture for integrating diverse geospatial data repositories has been proposed using service-based methodology. The semantic issues for discovery and retrieval of geospatial data over distributed geospatial services have also been proposed in the paper. The proposed architecture utilizes the ontological concepts for service description and subsequent discovery of services. An approach for semantic similarity assessment of geospatial services has been discussed

Geopan at@s: A brokering based gateway to georeferenced historical maps for risk analysis

Importance of ancient and historical maps is nowadays recognized in many applications (e.g., urban planning, landscape valorisation and preservation, land changes identification, etc.). In the last years a great effort has been done by different institutions, such as Geographical Institutes, Public Administrations, and collaborative communities, for digitizing and publishing online collections of historical maps. In spite of this variety and availability of data, information overload makes difficult their discovery and management: Without knowing the specific repository where the data are stored, it is difficult to find the information required. In addition, problems of interconnection between different data sources and their restricted interoperability may arise. This paper describe a new brokering based gateway developed to assure interoperability between data, in particular georeferenced historical maps and geographic data, gathered from different data providers, with various features and referring to different historical periods. The developed approach is exemplified by a new application named GeoPAN Atl@s that is aimed at linking in Northern Italy area land changes with risk analysis (local seismicity amplification and flooding risk) by using multi-Temporal data sources and historic maps

An Approach for Service Oriented Discovery and Retrieval of Spatial Data

ABSTRACT Successful information integration and sharing data across disparate systems and designs are required for fast access to and interpretation of many types of geospatial information. Spatial data are highly heterogeneous -not only they differ from data representation and storage methods, but they also differ in the way of querying the data. Finding and accessing spatial data in an environment like this is a crucial task. Enterprise geographic information system (E-GIS) is an organization-wide approach to GIS implementation, operation, and management. The main focus of the paper is to integrate diverse spatial data repositories for geographic applications using service-based methodology. We have adopted service-oriented architecture (SOA) for the discovery and retrieval of geospatial data. The architecture uses a central ontology as metadata information, which acts as service broker. Ontology-based discovery and retrieval of geographic data solves the problem of semantic heterogeneity, the major bottleneck for spatial interoperability. The implementation is in compliant with the Web Map Service (WMS) and Web Feature Service (WFS), the web service standards proposed by OGC. The need for loosely coupled service-based access of data in the spatial domain has been exploited. A query processing mechanism in distributed environment of spatial data sources has been discussed at the end. The proposed system has been implemented and fully tested

Geospatial Web Services, Open Standards, and Advances in Interoperability: A Selected, Annotated Bibliography

This paper is designed to help GIS librarians and information specialists follow developments in the emerging field of geospatial Web services (GWS). When built using open standards, GWS permits users to dynamically access, exchange, deliver, and process geospatial data and products on the World Wide Web, no matter what platform or protocol is used. Standards/specifications pertaining to geospatial ontologies, geospatial Web services and interoperability are discussed in this bibliography. Finally, a selected, annotated list of bibliographic references by experts in the field is presented