Sensor Web Enablement (SWE) for citizen science

In this thesis, concepts for developing Spatial Data Infrastructures with an emphasis on visualizing 3D landscape and city models in distributed environments are discussed. Spatial Data Infrastructures are important for public authorities in order to perform tasks on a daily basis, and serve as research topic in geo-informatics. Joint initiatives at national and international level exist for harmonizing procedures and technologies. Interoperability is an important aspect in this context - as enabling technology for sharing, distributing, and connecting geospatial data and services. The Open Geospatial Consortium is the main driver for developing international standards in this sector and includes government agencies, universities and private companies in a consensus process. 
\n3D city models are becoming increasingly popular not only in desktop Virtual Reality applications but also for being used in professional purposes by public authorities. Spatial Data Infrastructures focus so far on the storage and exchange of 3D building and elevation data. For efficient streaming and visualization of spatial 3D data in distributed network environments such as the internet, concepts from the area of real time 3D Computer Graphics must be applied and combined with Geographic Information Systems (GIS). For example, scene graph data structures are commonly used for creating complex and dynamic 3D environments for computer games and Virtual Reality applications, but have not been introduced in GIS so far. 
\nIn this thesis, several aspects of how to create interoperable and service-based environments for 3D spatial data are addressed. These aspects are covered by publications in journals and conference proceedings. The introductory chapter provides a logic succession from geometrical operations for processing raw data, to data integration patterns, to system designs of single components, to service interface descriptions and workflows, and finally to an architecture of a complete distributed service network.
\nDigital Elevation Models are very important in 3D geo-visualization systems. Data structures, methods and processes are described for making them available in service based infrastructures. A specific mesh reduction method is used for generating lower levels of detail from very large point data sets. An integration technique is presented that allows the combination with 2D GIS data such as roads and land use areas. This approach allows using another optimization technique that greatly improves the usability for immersive 3D applications such as pedestrian navigation: flattening road and water surfaces. It is a geometric operation, which uses data structures and algorithms found in numerical simulation software implementing Finite Element Methods. 
\n3D Routing is presented as a typical application scenario for detailed 3D city models. Specific problems such as bridges, overpasses and multilevel networks are addressed and possible solutions described. The integration of routing capabilities in service infrastructures can be accomplished with standards of the Open Geospatial Consortium. An additional service is described for creating 3D networks and for generating 3D routes on the fly. Visualization of indoor routes requires different representation techniques.
\nAs server interface for providing access to all 3D data, the Web 3D Service has been used and further developed. Integrating and handling scene graph data is described in order to create rich virtual environments. Coordinate transformations of scene graphs are described in detail, which is an important aspect for ensuring interoperability between systems using different spatial reference systems. The Web 3D Service plays a central part in nearly all experiments that have been carried out. It does not only provide the means for interactive web-visualizations, but also for performing further analyses, accessing detailed feature information, and for automatic content discovery.
\nOpenStreetMap and other worldwide available datasets are used for developing a complete architecture demonstrating the scalability of 3D Spatial Data Infrastructures. Its suitability for creating 3D city models is analyzed, according to requirements set by international standards. A full virtual globe system has been developed based on OpenStreetMap including data processing, database storage, web streaming and a visualization client.
\nResults are discussed and compared to similar approaches within geo-informatics research, clarifying in which application scenarios and under which requirements the approaches in this thesis can be applied.
\n

Environmental monitoring and evaluation (M&E) systems are indispensable tools for sustainable land management, especially in dry and fragile ecosystems. The reporting and dissemination of its products and indicators are the key roles to perform their missions. Furthermore, the overall success of such multilateral projects and networks depends on well-organized infrastructures for spatial data management. A spatial data infrastructure (SDI) is an efficient framework to centralize the management of spatial data and information related to multilateral projects for the best sharing and exchange between partners and stakeholders in order to ensure that they are interactively connected to use the data efficiently and in a flexible manner. This paper outlines the work undertaken in partnership between the Geography and GIS Department of the Faculty of Arts, King Abdulaziz University, Saudi Arabia Kingdom, the Geomatics, Earth and Land Settlement Branch of the Department of Geology, Faculty of Sciences of Tunis, Tunis El Manar University, Tunisia, and the Sahara and Sahel Observatory OSS which is an intergovernmental organization, in order to build a Spatial Data Infrastructure (SDI) for the ROSELT/OSS program (Long-Term Environmental Monitoring Observatories Network in the Circum-Sahara of the Sahara and Sahel Observatory). This SDI is entirely developed using Open Source technologies and the extensive suite of OGC (Open Geospatial Consortium) standards and specifications, to enable interoperability among and between its different components.

The development of a National Spatial Data Infrastructure (NSDI) represents a critical advancement in the management and accessibility of geospatial data, facilitating informed decision-making across sectors such as government administration, environmental monitoring, and urban planning { (Rajabifard and Williamson 2003), (Rajabifard and Williamson 2002), (Nebert 2001)}.In the context of Armenia, establishing a robust NSDI is particularly important, given the country's need to modernize its spatial data infrastructure and align with international standards, such as the European INSPIRE Directive (European Commission, 2007).One of the key components of this effort is the standardization of spatial data layers, which is essential for ensuring the effective use of data in various applications ranging from urban planning to environmental protection and resource management.This research focuses on developing a methodology for the standardization of basic layers in Armenia's NSDI, which are critical for the country's geospatial data infrastructure.These basic layers include administrative boundaries, real estate data (cadastral data), land valuation, property rights, land use (land cover), addresses, geographical names, surface water data, elevation models, relief, and transport infrastructure.Standardizing these layers involves creating consistent and interoperable datasets that can be utilized across various sectors, including land administration, environmental monitoring, disaster management, and infrastructure planning.The proposed methodology follows best practices outlined in international frameworks such as the INSPIRE Directive (European Parliament and Council, 2007), the ISO 19100 series of geographic information standards (ISO, 2002), and the Open Geospatial Consortium (OGC) standards (OGC, 2020), ensuring that the basic spatial data layers adhere to both national and international interoperability requirements.The methodology developed in this study consists of four key stages: (1) Data Collection and Preparation-gathering raw spatial data from a variety of sources, including orthophotos and existing topographic maps, to ensure comprehensive and up-to-date information; (2) Attribute Definition-establishing the mandatory attributes for basic spatial data layers based on NSDI standards for Armenia, ensuring completeness, consistency, and interoperability with other datasets {(Nogueras-Iso, Zarazaga, and Muro-Medrano 2005), (Tth et al. 2012), (Hadzilakos et al. 2000) }; (3) Data Structuring and Conversion-transforming raw data into standardized formats such as vector and raster formats, ensuring compatibility with NSDI requirements, and using standardized coordinate systems and metadata formats {(Heimovi, Marasovic, and Tavra 2014), (Rao et al. 2002)}; (4) Data Integration-combining basic spatial data layers with each other, such as administrative boundaries, land use, surface water, elevation models, and other relevant data, to create a cohesive and interoperable spatial database that can be used for multi-disciplinary applications.By following these stages, the research aims to contribute to the successful implementation of standardized and accessible basic spatial data layers within Armenia's NSDI framework.This approach not only aims to meet Armenia's national standards but also aligns with international initiatives for spatial data infrastructure development, ultimately enhancing the quality and availability of basic spatial data layers for a wide range of applications {(Craglia and Annoni 2006), (Kotsev et al.

A pilot regional Spatial Data Infrastructure (SDI) has recently been developed for the Heraklion Prefecture in Crete, Greece, using Geographic Free and Open Source Software (GeoFOSS). This SDI is compatible with the geospatial standards and specifications introduced by the Open Geospatial Consortium (OGC) and it distributes the geospatial content on the web through widely accepted services (e.g., WMS, WFS, WCS and CSW). This paper presents the architecture, the components and the functionality of the Heraklion SDI. Specifically, it focuses on the map server, along with the services that provide accessibility to the data repositories, the spatial database server, the metadata and data catalog, the visualization tools and the web-client interface.

The Open Geospatial Consortium (OGC) has conducted much work in the past on event-based models and architectures. However, the current OGC standard baseline only supports synchronous web service capabilities, which have insofar primarily addressed the request/reply model, where a client makes a request and the server usually responds synchronously, with either the requested information or a failure. Recently, the OGC Publish/Subscribe 1.0 Standard has introduced an abstract model for publish/subscribe message exchange, a long-awaited building block in the OGC suite of geospatial standards. The publish/subscribe pattern is distinguished from the request/reply one by the asynchronous delivery of messages and the ability for a client to specify an ongoing, persistent expression of interest. In this work, we report on the experimentation of the new OGC Publish/Subscribe 1.0 Standard in the context of the OGC Testbed-12 initiative and related fields of work, particularly in the application domains of Sensor Web and Aviation. We illustrate and discuss the enhancements in comparison to previous OGC service architectures, highlighting the benefits of introducing the PubSub 1.0 Standard into the considered systems and their workflows.

VGI-based spatial data infrastructure for land administration

Abstract. The aim of a spatial data infrastructure (SDI) is to make data available for the economical and societal benefit to a wide audience. A geoportal typically provides access to spatial data and associated web services in an SDI, facilitating the discovery, display, editing and analysis of data. In contrast, a spatial information infrastructure (SII) should provide access to information, i.e. data that has been processed, organized and presented so as to be useful. Thematic maps are an example of the representation of spatial information. An SII geoportal requires intelligence to orchestrate (automatically coordinate) web services that prepare, discover and present information, instead of data, to the user. We call this an intelligent geoportal. The Open Geospatial Consortium's Web Processing Service (WPS) standard provides the rules for describing the input and output of any type of spatial process. In this paper we present the results of an evaluation of two orchestration platforms: the 52° North framework and ZOO project. We evaluated the frameworks' orchestration capabilities for producing thematic maps. Results of the evaluation show that both frameworks have potential to facilitate orchestration in an intelligent geoportal, but that some functionality is still lacking; lack of semantic information and usability of the framework; these limitations creates barriers for the wide spread use of the frameworks. Before, the frameworks can be used for advance orchestration these limitations need to be addressed. The results of our evaluation of these frameworks, both with their respective strengths and weaknesses, can guide developers to choose the framework best suitable for their specific needs.

Ensuring effective Ambient Intelligence based upon the wide range of static as well as real-time datasets required to manage a transport infrastructure such as a motorway, is a daunting task. This paper presents how this challenge has been faced through the development of a service-based networked infrastructure capable to make a wide range of Geographical Information (GI) available to the operators of a major Italian motorway. In doing so, the system has used open standards from ISO and Open Geospatial Consortium. Unlike current Spatial Data Infrastructures (SDIs), which address relatively static data in time slices, the work presented allows, similarly to traditional GIS, to manage true dynamic data available through geo-referenced sensors along the motorway. The main objective of the project described within this paper was to link existing systems and networks to deliver a comprehensive, coordinated and sustained intelligent infrastructure which can be used to improve management of the motorway as a system. This approach follows the vision of Ambient Spatial Intelligence, which explores how to better embed intelligent features to respond to spatio-temporal queries and to better monitor geographical events within built and natural environments. The combination of information available from different sources (GI, sensor networks, etc.) with information on traffic and vehicle situation is essential to provide context awareness to operators. The networked platform developed has extended the traditional concept of SDIs with an unprecedented volume of real-time geo-referenced sensor data, deployed along the motorway path, all characterized by high spatial and temporal resolution.

The necessity of open standards for effective sharing and use of remote sensing continues to receive increasing emphasis in policies of agencies and projects around the world. Coordination on the development of open standards for geospatial information is a vital step to insure that the technical standards are ready to support the policy objectives. The mission of the Open Geospatial Consortium (OGC) is to advance development and use of international standards and supporting services that promote geospatial interoperability. To accomplish this mission, OGC serves as the global forum for the collaboration of geospatial data / solution providers and users. Photogrammetry and remote sensing are sources of the largest and most complex geospatial information. Some of the most mature OGC standards for remote sensing include the Sensor Web Enablement (SWE) standards, the Web Coverage Service (WCS) suite of standards, encodings such as NetCDF, GMLJP2 and GeoPackage, and the soon to be approved Discrete Global Grid Systems (DGGS) standard. In collaboration with ISPRS, OGC working with government, research and industrial organizations continue to advance the state of geospatial standards for full use of photogrammetry and remote sensing.

Emerging developments in geographic information systems and distributed computing offer a roadmap towards an unprecedented spatial data infrastructure in the climate sciences. Key to this are the standards developments for digital geographic information being led by the International Organisation for Standardisation (ISO) technical committee on geographic information/geomatics (TC211) and the Open Geospatial Consortium (OGC). These, coupled with the evolution of standardised web services for applications on the internet by the World Wide Web Consortium (W3C), mean that opportunities for both new applications and increased interoperability exist. These are exemplified by the ability to construct ISO‐compliant data models that expose legacy data sources through OGC web services. This paper concentrates on the applicability of these standards to climate data by introducing some examples and outlining the challenges ahead. An abstract data model is developed, based on ISO standards, and applied to a range of climate data –both observational and modelled. An OGC Web Map Server interface is constructed for numerical weather prediction (NWP) data stored in legacy data files. A W3C web service for remotely accessing gridded climate data is illustrated. Challenges identified include the following: first, both the ISO and OGC specifications require extensions to support climate data. Secondly, OGC services need to fully comply with W3C web services, and support complex access control. Finally, to achieve real interoperability, broadly accepted community‐based semantic data models are required across the range of climate data types. These challenges are being actively pursued, and broad data interoperability for the climate sciences appears within reach. Copyright © 2005 Royal Meteorological Society.

<p>The Platform for Atlantic Geohazard Risk Management (AGEO) is a new project co-financed under the Interreg Programme for the Atlantic Area which aims to launch five Citizens’ Observatory pilots on geohazards according to regional priorities:</p><ul><li>Citizens’ observatory on rockfalls and rockfall-triggers in the <strong>Canary Islands, Spain</strong></li> <li>Peat-slides and peat massmovement monitoring and control in <strong>Cuilcagh Mountain, Northern Ireland</strong></li> <li>Multihazard Citizens’ Observatory in <strong>Lisbon, Portugal</strong></li> <li>Citizens’ observatory of slope instability monitoring along the <strong>Cliffs of Moher, Ireland</strong></li> <li>Citizens’ observatory of vulnerability to coastal Risks in <strong>Brittany, france</strong></li> </ul><p>These will demonstrate how citizens’ involvement in geohazard risks prevention can strengthen regional and national risk management systems. Instituto Superior Técnico (Portugal) leads the consortium of AGEO that also counts with several other partners from Portugal, Spain, France, Ireland and the United Kingdom.</p><p>AGEO will engage with local communities to actively participate in risk preparedness and monitoring and incorporate local capacities into risk management systems. Experiences gained during the implementation of the Citizens’ Observatory pilots will be used to formulate recommendations for the creation of future observatories in response to the widest range of hazards (both natural and human-induced) faced in the Atlantic region.</p><p>The Observatories are part of the phenomenon of citizen science.  As defined by the EC, “Citizens' Observatories are community-based environmental monitoring and information systems. They build on innovative and novel Earth observation applications embedded in portable or mobile personal devices.  This means that citizens can help and be engaged in observing our environment.”</p><p>There are many other definitions, as it is still a novel concept, but for this project the one above will be used. It is an observatory in a sense that we need careful monitoring of the risks that will be defined per region in line with a set of parameters to be defined through engaging with participating citizens to be filled in by the participating citizens. This approach lends the opportunity of collecting large amounts of data for very little to no money with the added bonus of the territorial coverage such approach can grant. Additionally, spatial data infrastructures and services already in place, e.g. Copernicus, will support the assessment and monitoring of geohazards and risk management systems.</p><p>AGEO is also organizing workshops in each participating region to ensure the citizens understand the role they play in preventing and mitigating natural risks by being part of the observatories and hopefully encouraging new members to join. These workshops will be held in the national language of the region and are to be tailored to the different audiences and will democratize the use of the observatories by listening to the people using them and taking into account their needs.</p><p> </p><div> <div> <div> </div> </div> </div>

This work presents the development of an efficient tool for managing, visualizing, analysing, and integrating with other data sources, the deformation time-series obtained by applying the advanced differential interferometric synthetic aperture radar (DInSAR) techniques. To implement such a tool we extend the functionalities of GeoNode, which is a web-based platform providing an open source framework based on the Open Geospatial Consortium (OGC) standards, that allows development of Geospatial Information Systems (GIS) and Spatial Data Infrastructures (SDI). In particular, our efforts have been dedicated to enable the GeoNode platform to effectively analyze and visualize the spatio/temporal characteristics of the DInSAR deformation time-series and their related products. Moreover, the implemented multi-thread based new functionalities allow us to efficiently upload and update large data volumes of the available DInSAR results into a dedicated geodatabase. The examples we present, based on Sentinel-1 DInSAR results relevant to Italy, demonstrate the effectiveness of the extended version of the GeoNode platform.

Increasing availability of geo-spatial data, enabled by improvement of technologies in the field of spatial data collection, provides unprecedented opportunities in knowledge creation and distribution. Beside the integration of distributed spatial data, available in Spatial Data Infrastructures (SDIs), proper processing of data is crucial for knowledge discovery. This work proposes an ontology based spatial knowledge discovery framework based on Open Geospatial Consortium (OGC) standards. Data processing in geo-spatial domain is done using spatial clustering algorithm. It is implemented as the web processing service of this framework. Prediction of urban house price is taken as the case study.

The quite new Web Processing Service (WPS) specification of the Open Geospatial Consortium (OGC) is increasing the value of Spatial Data Infrastructures (SDIs) by offering a standard for the actual processing of spatial data. The interface is already used in a range of projects, but up to now mainly in connection with 2D spatial data. In this paper we want to demonstrate that the standard can also be applied in a 3D environment which increases the potential of such 3DSDIs. We implemented two use cases of disaster management and environmental monitoring and discuss the benefits and drawbacks of applying geoprocessing functionality in 3D. The scenarios were integrated and visualized in a Web3D Server (W3DS) viewer and demonstrate how useful it is to present the outcomes of such simulations in the third dimension.

A web-based distributed system for monitoring and forecasting of the marine environment has been developed in line with INfrastructure for SPatial InfoRmation in Europe (INSPIRE) and Global Monitoring for Environment and Security (GMES) recommendations for a European Spatial Data Infrastructure (SDI). This system, called DISPRO, enables integration and distribution of multi-source data from satellites, aircraft, and in situ instruments, as well as results from numerical models. Geographic data and metadata are stored on a set of distributed computer nodes and retrieved and integrated by a web GIS client by means of Open Geospatial Consortium (OGC) Web Map Server (WMS) technologies. A profile of ISO 19115 was developed for metadata handling, using eXtensible Markup Language (XML) as a platform independent encoding mechanism. DISPRO has been demonstrated in six European coastal zone and ocean regions in the spring and summer of 2005. The overall positive experiences of both service providers and end users indicate that the system should be further developed into an operational GMES service.