Web service based Grid workflow application in quantitative remote sensing retrieval

Open source REST services for environmental sensor networking

Spatial Data Infrastructures often maintain directories of public geospatial Web Services built from Web services listed in their registries. However, registry data may be stale and incomplete because their maintenance depends on service owners. A solution is to back the registry with an active directory, or index, that lists Web services found by a Web crawler focused on geospatial Web services. The problem of the identification of the geospatial nature of a Web service appears when such crawler finds a service described in the Web Services Description Language (WSDL). This paper presents two components required to build an active directory: a crawler focused on Open Geospatial Consortium and WSDL-based Web services, and an unsupervised classifier of geospatial Web services described in WSDL.

The Geospatial data has been used extensively in many scientific areas but a lot of issues arise for sharing and processing such large amount of data. The geospatial data is exposed most of the time using geospatial Web services, standardized by the Open Geospatial Consortium (OGC). In this paper we discuss solutions and approaches, based on the integration of OGC Web services into the Grid environment, for solving those problems in the context of enviroGRIDS project. The interoperability between the OGC and Grid technologies is promising in solving important challenges in Earth Observation (EO) environment and is discussed at different levels in the project architecture: data level, execution/processing level and portal level.

The applications of Geographic Information System (GIS) in the education sector are increasing day by day. The geospatial information can be published, discovered, searched, analyzed, and displayed through webGIS-based applications. Lack of an open source geospatial resource-based platform for data sharing, discovery, and service delivery in the education sector is a critical issue in managing the education of large population in India. The use of open geospatial consortium (OGC) developed open standards for geospatial web services will result in the interoperability of geographic information. In this paper, an interoperable and secure service-oriented architecture (SOA)-based webGIS framework is developed to handle the technical and non-technical issues in the education sector. In this research work, spatial analysis on schools is performed along with the design and development of webGIS framework using SOA, OGC standards, and open source software. The developed webGIS framework, acronym as EduGIS, is interoperable and secure which is implemented for the education sector. The development of webGIS framework is based upon three-tier thin client architecture. The present research work has investigated an optimized adoption of various free and open source software like Quantum GIS, GeoServer, Apache Tomcat, PostGIS, and uDig in different tiers of developed webGIS framework. The interoperability of developed EduGIS ensures that it can be shared across different technologies, data, platforms, and organizations. The development of open source-based webGIS framework will serve as a means of reducing licensing costs in developing countries like India and will promote indigenous technological development for primary education in rural areas.

The objective of this project is to evaluate existing and emerging Open Geospatial Consortium (OGC) standards for use in LLNL programs that rely heavily on geographic data. OGC standards are intended to facilitate interoperability between geospatial processing systems to avoid duplication of effort, lower development costs, and encourage competition based on improved capability and performance rather than vendor lock-in. Some of these standards appear to be gaining traction in the geospatial data community, the Federal government, DOE and DHS. A serious evaluation of this technology is appropriate at this time due to increasing interest and mandated compliance in the Federal government in some situations. A subset of OGC standards is identified and reviewed with a focus on applications to LLNL programs. Each standard or recommendation reviewed was evaluated in general terms. In addition, for specific programs such as Gen&SIS and NARAC, a specific evaluation was made of several of the standards and how they could be used most effectively. It is also important to evaluate the acceptance of these standards in the commercial arena. The implementation of OGC standards by the largest GIS vendor (ESRI) was reviewed. At present, OGC standards are primary useful in specific situations. More generally, many of the standards are immature and their impact on the government and commercial sectors is unclear. Consequently, OGC and related developments need to be observed. As specific standards or groups of standards mature and establish their relevance, these can also be incorporated in LLNL programs as requirements dictate, especially if open implementations and commercial products are available.

Interoperability is the main challenge on the way to efficiently find and access spatial data on the web. Significant contributions regarding interoperability have been made by the Open Geospatial Consortium (OGC), where web service standards to publish and download spatial data have been established. The OGCs GeoSPARQL specification targets spatial data on the Web as Linked Open Data (LOD) by providing a comprehensive vocabulary for annotation and querying. While OGC web service standards are widely implemented in Geographic Information Systems (GIS) and offer a seamless service infrastructure, the LOD approach offers structured techniques to interlink and semantically describe spatial information. It is currently not possible to use LOD as a data source for OGC web services. In this chapter we make a suggestion for technically linking OGC web services and LOD as a data source, and we explore and discuss its benefits. We describe and test an adapter that enables access to geographic LOD datasets from within OGC Web Feature Service (WFS), enabling most current GIS to access the Web of Data. We discuss performance tests by comparing the proposed adapter to a reference WFS implementation.

Monitoring the environment is critical for scientists to understand the environmental dynamics. However, the traditional monitoring systems such as sensor networks are usually labor-intensive and complicated to deploy. As the concept of citizen sensing has been proposed to include volunteers into the environmental monitoring systems, a key to realize the citizen sensing vision is to empower citizens with the low-cost and easy-to-use sensing devices. In this paper, we focus on two technologies that have the potential to realize the citizen sensing vision: the Internet of Things (IoT) and the world-wide sensor web. In order to address the issues from the decentralized and heterogeneous nature of IoT devices and sensors, we propose the TinySOS service, a tiny web server hosting a light-weight profile of Open Geospatial Consortium (OGC) Sensor Observation Service (SOS). By hosting open standard sensor web services on the IoT devices, not only the devices become self-describable, self-contained, and interoperable, but also the collected observations are accessible via the Internet as soon as they are measured. In this case, the sensor web can provide real-time sensor data streams in a much higher spatial and temporal resolution, which consequently allows scientists to observe phenomena that were previously unobservable.

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.

A geotagged Short Message Service (SMS), such as those following Open Geospatial Consortium (OGC) Open GeoSMS (OGS) standard, is useful for many applications that require location based services field work. In OGS specification, a geotag is used as a hyperlink for retrieving detail information of given target at given location. This feature meets the interoperation requirements of time-sensitive, location-aware notification and monitoring services. This feature can give service providers to design more various and useful service scenarios, and these requirements make importantly to develop vendor specific Apps for realizing these service scenarios. A design pattern for OGS mobile client Apps will help to develop the Apps with relatively less effort. This paper focuses on a design for an OGS mobile client App and shows a Connector-Translator-Launcher (CTL) flow for smartphone environments. The CTL flow based mobile client App is based on Model-View-Controller (MVC) model. It applies pluggable modules for connecting geospatial services pointed by each geotag and translating geospatial content retrieved from such services. The App displays details information specified by a geotag following the OGS. The Android-based mobile client App was developed for OGC's OGC Web Services, Phase 8 (OWS-8). It was applied as a mobile tracking client in geospatial web service testbed scenarios for the Observation Fusion (Tracking) thread. Two pluggable modules were developed for the scenario application. One is a connector module for connecting to a track server, and another is a translator module for translating track information for displaying on map views.

This paper describes an approach for mediating the differences between the Geospatial domain and the Grid environment and creating an interoperable communication between these two platforms. The interoperability between the Geospatial Web services and the Grid infrastructure is part of the enviroGRIDS project and promises to solve important problems from the Earth Observation field, dealing with processing and storing large amounts of data and performing computationally intensive and complex calculations while achieving high performances. The Geospatial Web services, standardized by the Open Geospatial Consortium are adapted to support different execution flows, both on Web and gLite Grid middleware, to maximize the obtained performances.

Geospatial web services within a scientific workflow: Predicting marine mammal habitats in a dynamic environment

Web services provide users ever better methods to access and use Earth Observation data. Development of a web services architecture for the Global Earth Observing System of Systems was conducted using an evolutionary development process that depended on standards for geospatial web services. Standards for geospatial web services provide interfaces that can be scaled to global deployment. The GEOSS Architecture Implementation Pilot defined an evolutionary development process and reusable architecting methods for applying web services to a global scale system of systems for Earth observations. ISO/IEC, OGC and other standards are used by the AIP architecture to meet the objectives of GEOSS to enable comprehensive, coordinated and sustained observation of the Earth and also efficient publication and use of the collected information.

This article intends to provide an advanced traveller information system based on open geospatial consortium (OGC) standards to perform a fuzzy bi-criteria shortest-path analysis for a multimodal transportation network. To do so, chaining of OGC web services is used to resolve interoperability problems among distributed and heterogeneous resource data. First, a web feature service is assigned to each mode of transportation to gather and convert the data to a standard format, such as geographic markup language. Then, the obtained data are combined to model and construct the multimodal transportation network. Subsequently, a web processing service is designed for performing a fuzzy bi-criteria shortest-path analysis in the multimodal transportation network. Finally, the best routes between the origin–destination pair are presented on a digital map by using a web map service. In the study, among various route-selection criteria, travel time and comfort are considered. To model these criteria, the fuzzy set theory is utilized. By using fuzzy decision tables and a Tsukamoto fuzzy inference system, the desirability of the routes is calculated. The results of comparison among the four travel routes between various origin–destination pairs indicate that the proposed system could be an applicable tool for providing pre-trip information and assisting multimodal travellers under uncertain conditions.

Using SensorML to construct a geoprocessing e-Science workflow model under a sensor web environment

Spatial Data Infrastructures (SDI) have been widely accepted to exchange geospatial data among organizations. Today SDIs main focus lies on the provision of geospatial data in the form of distributed spatial web services, the retrieval through catalogues, and visualization in the form of Web Map Services (WMS). The hypothesis presented in this paper takes SDI's one step further by providing a method to process geodata in an Open Geospatial Consortium (OGC) compliant way into information. Two case studies present the potential of standardized geoprocessing services. In addition, this paper addresses the problem of service chaining by providing a system architecture to implement complex geoprocessing models and workflows based on web services using Web Service Orchestration (WSO). The proposed methods utilize spatial standards provided by OGC, the International Organization for Standardization (ISO) and ‘mainstream IT’ standards provided by the World Wide Web Consortium (W3C) and the Organization for the Advancement of Structured Information Standards (OASIS) to establish a generic web service architecture for providing common geoprocessing capabilities (e.g. spatial algorithms, map algebra, etc.) for usage in SDIs.