191 research outputs found
Extending THREDDS middleware to serve OGC community
International audienceAs far as interoperability is concerned, in a service-oriented framework, it is possible to distinguish different service tiers; each tier contains systems and tools which implement that tier's specific task. The present paper analyses such a framework for the Earth Sciences and the GIS information communities. For the Earth Sciences community, the heterogeneity of existing protocols and data models is outlined, considering the experience of the Unidata community. For the GIS community, the interoperability opportunities laid by the OGC's specifications are briefly introduced. The need of achieving the two communities' frameworks interoperability, and its importance for science Digital Library applications are introduced. A solution is presented and discussed; it is based on the following technologies: THREDDS Data Server, OGC WCS/WFS and ncML-GML. An OGC interoperability experiment, which tests the proposed solution, is briefly presented
Mediation to deal with information heterogeneity ? application to Earth System Science
International audienceWe address the problem of data and information interoperability in the Earth System Science information domain. We believe that well-established architectures and standard technologies are now available to implement data interoperability. In particular, we elaborate on the mediated approach, and present several technological aspects of our implementation of a Mediator-based Information System for Earth System Science Data. We highlight some limitations of current standard-based solutions and introduce possible future improvements
Editorial "Earth and Space Science Informatics: informatics in oceanography"
A decade ago, information was discrete and disconnected, assembling data from many different sources was inherently time consuming, and was made for specific studies, such as evaluation of trends in ecosystems, climatology productions, etc. Most of the data were not directly accessible, but were sent by mail on CD-ROMs or floppy discs. The world is changed and the collection of digital data is growing at an exponential rate, making the access to data more difficult than before. During the last decade, with the advent of Internet-based system architectures a fundamental shift has occurred. The digitization of all kinds of data, the implementation of computer networks and the availability of broad band have posed the basis for the connection of a vast amount of data and information. Internet, Web, distributed information systems and computing infrastructures have been changing the working way in science, engineering, business, and education. Today, advances in all kind of application domains is often related with the possibilities to access heterogeneous information and the related tools to understand and use them. Different scientific and technological communities are today working together to develop federated information systems by applying interoperability solutions and recognising that: â Data in the Earth sciences is being used by a far broader community than ever before. â Information harvesting by selecting the appropriate, exchange metadata, the evolving interoperability standards, and the multi-disciplinary scenarios raises important and difficult challenges
A Simple Biomimetic Receptor Selectively Recognizing the GlcNAc2 Disaccharide in Water
AbstractGlcNAc2 is the core disaccharide fragment present in Nâglycans exposed on the surface of enveloped viruses of high health concern, such as coronaviruses. Because Nâglycans are directly involved in the docking of viruses to host cells, recognition of GlcNAc2 by a biomimetic receptor may be a convenient alternative to the use of lectins to interfere with viral entry and infection. Herein, we describe a simple biomimetic receptor recognizing the methylâÎČâglycoside of GlcNAc2 in water with an unprecedented affinity of 160â
ÎŒM, exceeding that of more structurally complex receptors reported in the literature. The tweezersâshaped acyclic structure exhibits marked selectivity among structurally related disaccharides, and complete discrimination between monoâ and disaccharides. Molecular modelling calculations supported by NOE data provided a threeâdimensional description of the binding mode, shedding light on the origin of the affinities and selectivities exhibited by the receptor
Federated data bases for the development of an operational monitoring and forecasting system of the ocean: the THREDDS Dataset Merger
During the last decade, operational monitoring and forecasting systems have been developed in all the European seas. The exchange of data and products and the development of services for a wide community of users pose some fundamental issues, whose solution has become a priority in integrated and GMES referring projects, such as the MERSEA European project. These projects aim to develop a European system for operational monitoring and forecasting on global and regional scales of ocean physics, bio-chemistry and ecosystems. GMES system and its operational projects need to federate resources and expertise coming from diverse organizations working on different Earth Sciences fields (e.g. satellite data processing, in situ observing systems, data management, ocean and ecosystem modeling, etc.). Therefore, it is required a Marine Information Management (MIM) system capable of facilitating the regular real-time exchange of high quality information, data and products. Moreover, MIM system must provide appropriate information for a wide range of external users both in real-time and delayed mode. </p><p style="line-height: 20px;"> In this paper an architecture based on the OPeNDAP/THREDDS technology is proposed as a solution for these operational systems. In this context, a catalog merging solution is introduced for the MIM system, which results in the design and development of the THREDDS Dataset Merger (TDM): a set of services meant to merge THREDDS Dataset Inventory Catalogs, so to achieve a unique catalog service for a whole database federation. TDM service merges distributed and autonomous THREDDS catalogs in order to work out a virtual merged catalog. The TDM service was extended in order to provide automatic catalogs synchronization. This service allows extending the pull-based TDM paradigm to support push-based applications. Some security issues are also considered
CDI/THREDDS interoperability in the SeaDataNet framework
Abstract. SeaDataNet is an EU funded project aiming to create and operate a pan-European, marine data infrastructure for managing the large and diverse datasets (i.e. temperature, salinity current, sea level, chemical, physical and biological properties) collected by the oceanographic fleets and the new automatic observation systems. In order to make the SeaDataNet system compliant with the INSPIRE Implementing Rules for discovery service, an ISO 19139 encoding of the SeaDataNet Common Data Index (CDI) metadata model was defined. Moreover, the problem of heterogeneous data sources has been addressed. In fact, a widely used system of SeaDataNet partners and oceanographic-marine community is THREDDS/OPeNDAP; this raises up the problem of federating into SeaDataNet framework THREDDS/OPeNDAP systems as well. In this paper we describe an interoperability framework to access resources (i.e. data and services) that are available through CDI and THREDDS/OPeNDAP services. The proposed solution implements a common catalog interface to discover and access the two heterogeneous resources in a common way. This catalog service is fully distributed and implements international standards as far as geospatial information discovery and query are concerned. The developed solution is called GI-cat and was experimented in the framework of the SeaDataNet European project
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