Thierry Badard

Merging Hypermedia GIS with Spatial On-Line Analytical Processing: Towards Hypermedia SOLAP

Geographic Knowledge Discovery (GKD) requires systems that support interactive exploration of data without being slowed down by the intricacies of a SQL-type query language and cryptic data structures. GKD requires to compare maps of different phenomena or epochs, to dig into these maps to obtain detailed information, to roll-up data for more global information and to synchronize maps with tables and charts. This can be done by combining the capabilities of GIS with those of OLAP, leading to SOLAP (Spatial OLAP). To enrich the GKD process, we added hypermedia documents to SOLAP. Hypermedia SOLAP provides a more global perception of the situation without requiring the advanced knowledge typically required by Hypermedia GIS. This chapter presents hypermedia SOLAP concepts and gives an example dealing with the erosion of lands and roads.

A conceptual framework to support semantic interoperability of geospatial datacubes

Today, we observe a wide use of geospatial databases that are implemented in many forms (e.g. transactional centralized systems, distributed databases, multidimensional datacubes). Among those possibilities, the multidimensional datacube is more appropriate to support interactive analysis and to guide the organizations strategic decisions, especially when different epochs and levels of information granularity are involved. However, one may need to use several geospatial multidimensional datacubes which may be heterogeneous in design or content. Overcoming the heterogeneity problems in a manner that is transparent to users has been the principal aim of interoperability for the last fifteen years. In spite of successful initiatives and widespread use of standards, todays solutions do not address yet geospatial datacubes. This paper aims at describing the interoperability of geospatial datacubes, defining the semantic heterogeneity problems that may occur when using different geospatial datacubes, and proposing a conceptual framework to support semantic interoperability of these datacubes.

Development of a Web Geological Feature Server (WGFS) for sharing and querying of 3D objects

In order to adequately fulfil specific requirements related to spatial database integration with 3D modeling tools, this paper presents the development of a generic and open system architecture called Web Geological Feature Server (WGFS). WGFS provides direct access through Web services to 3D geological models. WGFS is based on a three-tier architecture: a client (Gocad), an application server (Apache Tomcat and Deegree) and a DBMS (MySQL). This architecture takes advantage of standard-compliant spatial applications such as WFS and GML standards stemming from OGC and spatial schema from ISO TC/211-Geographic Information. Before introducing the architecture and motivations of some geoinformatics choices, we will remind some important issues that have to be taken into account when such development is planned.

Web services-oriented architectures for mobile SOLAP applications

With the growing popularity of mobile computing and the empowerment of mobile devices by high end-users and decision-makers, the development of architectures based on web services for the deployment of mobile Spatial OLAP (SOLAP) applications is being perceived as a powerful solution. This paper deals with geospatial (web) Services-Oriented Architectures (SOA) for mobile processing of geo-decisional information. The paper first reviews the underlying concepts of typical SOLAP applications as well as the general concepts of mobile computing. The existing SOLAP functionalities are presented and their viability/usefulness in a mobile environment are discussed. Different web services based on an extended geospatial SOA are then proposed in order to tackle the several issues related to mobile SOLAP. Finally, several research challenges and outlooks are discussed.

Enhancing the Mental Representations of Space Used by Blind Pedestrians, Based on an Image Schemata Model

The configuration of mental representation of space plays a major role in successful navigational activities. Therefore, navigational assistance for pedestrians who are blind should help them to better configure their mental representation of the environment. In this paper, we propose and exploit a computational model for the mental representation of urban areas as an aid to orientation and navigation for visually impaired pedestrians. Our model uses image schemata to capture the spatial semantics and configural elements of urban space necessary for this purpose. These image schemata are schematic structures that are continually requested by individuals in their perception, bodily movement and interaction with surrounding objects. Our proposed model also incorporates a hierarchical structure to provide different levels of detail tied to appropriate spatial perspectives at each scale. We presume that such computational model will help us to develop an appropriate structure of spatial data used to assist the target population. At the end of the paper, we illustrate the utility of our configural model by developing a typical scenario for the navigation of a blind pedestrian in an urban area.

Elcano: A Geospatial Big Data Processing System based on SparkSQL

Big data are in the midst of many scientific and economic issues. Furthermore, their volume is continuously increasing. As a result, the need for management and processing solutions has become critical. Unfortunately, while most of these data have a spatial component, almost none of the current systems are able to manage it. For example, while Spark may be the most efficient environment for managing Big data, it is only used by five spatial data management systems. None of these solutions fully complies with ISO standards and OGC specifications in terms of spatial processing, and many of them are neither efficient enough nor extensible. The authors seek a way to overcome these limitations. Therefore, after a detailed study of the limitations of the existing systems, they define a system in greater accordance with the ISO19125 standard. The proposed solution, Elcano, is an extension of Spark complying with this standard and allowing the SQL querying of spatial data. Finally, the tests demonstrate that the resulting system surpasses the current available solutions on the market.

Context-based mobile GeoBI: enhancing business analysis with contextual metrics/statistics and context-based reasoning

Business professionals are increasingly mobile and should be supported by suitable mobile Decision Support Systems (DSS). In our previous work, we have established that such suitable mobile DSS should be (i) GeoBI(Geospatial Business Intelligence)-enabled and (ii) context-based, and have addressed issues regarding context characterization and context modeling. The present paper deals with mobile GeoBI context-based reasoning. Through realistic scenarios, it highlights (i) the requirement for context-based reasoning to enhance mobile GeoBI experience, (ii) the need for contextual metrics/statistics to help mobile business professionals discover their local context, (iii) the need for crossing business performance metrics with contextual metrics to help mobile business professionals in discovering the context hidden behind business performance figures, and proposes convenient solutions to tackle these needs.

Une architecture orientée service web pour la constitution de minicubes SOLAP pour clients mobiles

Existing Spatial OLAP (SOLAP) applications are targeted towards desktop c omputer environments. In order to enable geospatial decision support in mobility c ontexts, SOLAP re- quires some modifications. This paper describes a solution, based on se rvice-oriented architec- tures and Web services technologies, designed to adapt SOLAP data cub es to the requirements and constraints encountered in mobile computing environments and wireles s networks.

UMapIT© (Unrestricted Mapping Interactive Tool): Merging the datacube paradigm with an occurrence-based approach to support on-demand web mapping

UMapIT is an on-demand web mapping tool that is being developed in an attempt to provide Internet users with flexible means to personalize maps and interactively navigate within them. Based on a specific multiple representation database structure, it offers new functionalities to be applied at the occurrence level. These innovative functionalities come from the datacube paradigm. They include geometric drills which allow the user to navigate between the different LoDs (Level of Detail) associated with an object or to the different geometries of a same LoD that are aimed at different purposes. These functionalities also address the semantic and graphic aspects as well, offering further flexibility to the users interested in navigating among the different meanings associated with an object or to change its visual variables (e.g., color, symbol) without affecting other occurrences of the same class. Furthermore, the underlying structure of UMapIT allows for the support of “GenZoom” operations that adjust each object’s geometry individually according to the map scale, simulating on-the-fly cartographic generalization. The objective of this chapter is to illustrate the new capabilities offered by merging the datacube paradigm with an occurrence-based approach for on-demand web mapping. Emphasis is given to fundamental concepts and to their implementation into UMapIT. Such merging of GIS and datacube concepts, which emerged from the Business Intelligence (BI) field, has raised a lot of interest and research funding in Canada, reflecting the evolution going on in this country from spatial data management (using transactional systems) towards highly flexible spatial analytical systems (using geospatial intelligence technologies). This chapter also provides a solution to the desire of Canadian organisations to offer better map-on-demand web services.