Eywa
Eywa (formerly UNIoTE) is a fog computing infrastructure that provides control and data planes for RDF stream processing to be performed on resource-constrained client, source and broker nodes.
Continuous queries are registered by clients in RSP-QL, an extension of the SPARQL query language.
The wiki contains more information of how UNIOTE works.
Eywa System:
Benchmarks:
PIOTRe: Personal IoT Repository, uses Eywa at its core to handle registering streaming SPARQL queries.