Basic Concepts

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gCube once deployed and installed implements a service that is characterised by some foundational concepts, i.e. Portal, Virtual Research Environment, Workspace and Content (Information Objects, Collections, Annotations and Metadata).

Community Portal

This is the "web site" acting as a point of access to the set of Virtual Research Environments operated by a gCube-based Infrastructure.

Virtual Research Environment

This is web-based working environment conceived to provide scientists with a collaborative framework enabling them to produce and exchange results with peers around the globe in cost-efficient manner. A VRE not only offers capabilities for accessing cross-disciplinary data and knowledge, it also provides services for exploiting a multiplicity of other disparate tools and computing resources enabling innovative analysis, simulation and domain specific knowledge generation processes.

Each VRE has its own offering with respect to available content and capabilities that is tailored to serve the needs of a specific scenario.

The set of facilities that might be offered via a VRE are described in the remainder of this guide.


A workspace represents a collaborative area in which users can exchange and organize information objects (items) according to their specific needs. Because of this, every user of any Virtual Research Environment is provided with this area. It resembles a classic folder-based file system. For further details, please refer to the dedicated page.

Content: Information Objects, Collections, Annotations and Metadata

The Content concept encompasses the data and information that the VRE handles and makes available to its users.

It is an umbrella concept used to aggregate all forms of information objects that a VRE collects, manages, and delivers, including such objects as annotations, and metadata.

Content is composed of a set of information objects organized into collections.

The notion of Information Object represents the main entity populating the Content of a Virtual Research Environment. An Information Object can be a complex, multimedia and multi-type object with parts, such as a sound recording associated with a set of slides, a music score, political and economic data associated with interactive simulations, a Ph.D. thesis which includes a representation of a performance, or a simulation experiment and the experimental data set adopted, a data stream representing the pool of data continuously measured by a sensor.

gCube supports the management of a number of information objects including Time Series Objects and AquaMaps Objects.

Collections represent the “classic” mechanism to organize Information Objects and to provide focused views of the VRE Content. They are sets of Information Objects aggregated for some management purposes, e.g. behave as a single entity for access rights management. Another typical role assigned to collections is organizing the search space into restricted and/or topic-based sub-sets of it, thus allowing improving the search results.

Content Annotation

As a definition of annotation we could say that it is a written explanation or criticism or illustration that is added to an information object. Informally, annotations are comments or notes made by users in order to expose their ideas about a document. The annotations’ role in a digital library is very important since they promote collaboration between the users of the library. Through annotations, new ideas and concepts can be discussed, something which may help the understanding of an annotated object and the advance of knowledge about it. For further information, please refer to the dedicated page.


Every Information Object is equipped with metadata. The “classic” definition of metadata is “data about other data”.

Metadata are used for describing different aspects of the data they are associated with, such as the semantics, provenance, constraints, parameters, content, quality, condition, and any other characteristic that is considered important to record. These data can be used in different contexts and for a diversity of purposes; usually, they are associated with an Information Object as a means for facilitating the effective discovery, retrieval, use and management of the object.

The gCube system does not impose any constraint on the metadata it supports, the system is capable to handle any piece of text. Each metadata object contains data described according to a specified schema and/or ontology in the large (any conceptualisation that defines the terms about a domain). In fact, a metadata object usually manifest in a metadata record, i.e. a number of items of information where each item as well the values assigned to the item might come from one or more controlled vocabularies. An example of metadata schema is Dublin Core, i.e. a vocabulary of fifteen properties for use in resource description. An excerpt of a Dublin Core metadata record in XML is as follows

<dc:creator>Rose Bush</dc:creator>
<dc:title>A Guide to Growing Roses</dc:title>
<dc:description>Describes process for planting and nurturing different kinds of rose bushes.</dc:description> 

However, multiple metadata schemas/ontologies exist and can be defined, each tailored or specifically designed to satisfy the needs of a well identified community.

Each Information Object might be equipped with an arbitrary number of metadata objects compliant with a specific schema.