Available as Online Component
Component Payola (UEP). Payola is a web application which lets you work with graph data in a new way. You can visualize Linked Data using several preinstalled plugins as graphs, tables, etc. Moreover, you can create an analysis and run it against a set of SPARQL endpoints. Analysis results are processed and visualized using the embedded visualization plugins.
Component PoolParty Thesaurus Manager (SWC). PoolParty is a thesaurus management system and a SKOS editor for the Semantic Web including text mining and linked data capabilities. The system helps to build and maintain multilingual thesauri providing an easy-to-use interface. PoolParty server provides semantic services to integrate semantic search or recommender systems into systems like CMS, DMS, CRM or Wikis.
Component PoolParty Extractor (SWC). The PoolParty Extractor (PPX) oﬀers an API providing text mining algorithms based on semantic knowledge models. With the PoolParty Extractor you can analyse documents in an automated fashion, extracting meaningful phrases, named entities, categories or other metadata. Diﬀerent data or metadata schemas can be mapped to a SKOS thesaurus that is used as a uniﬁed semantic knowledge model.
Component Sindice (DERI, OGL). Sindice is a state of the art infrastructure to process, consolidate and query the Web of Data. Sindice collates these billions of pieces of metadata into an coherent umbrella of functionalities and services. sindice.com
Available Online Data Sources
Table 1 provides an overview of the main data sources to which LOD2 has contributed.
The LOD2 Stack Components Functional Areas Coverage
When distributing the components over the Linked Data Publishing cycle functionalities the following Fig. 2 is obtained. In this ﬁgure the component is associated with its main role in the data publishing cycle. In the middle are placed the applications that are not dedicated to one area, such as the automatization platform UniﬁedViews, and the applications that exploit the LOD2 stack, such as the lod2demo and LOD2 Statistical Workbench. Online components are
Table 1. Online Data Sources supported by LOD2
marked with a globe icon. The cubed formatted components are dedicated components for the statistical domain. They are embedded in the LOD2 Statistical Workbench.
In this ﬁgure, we see that the current version of the stack has a high number of components geared towards the extraction, storage and querying parts. This can be explained by the large number of data formats that need to be transformed to RDF. Every component tackles a speciﬁc subset of these formats. Most of the other components contain a small selection of specialized tools for a speciﬁc task. In the search/browsing/exploration stage, every component has its own way of visualizing the data.