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6. Evaluation

7.4. Final Remarks

It is hoped by the author of this thesis that SUMMR, a methodology that supports performing all the mapping maintenance and reuse use cases and tasks, discovered and derived from the state of the art review in this thesis will be of benefit to the research community. The taxonomy of tasks and use cases will be useful for other researchers who wish to design an approach for mapping maintenance and reuse as it indicates what an approach should support. Researchers could also contribute to the taxonomy with new mapping maintenance and reuse use cases they may encounter in the future - further enriching it for additional researchers. SUMMR’s functionality (as a whole or aspects of it) could also be adopted as part of larger frameworks which require the maintenance or reuse of mappings in some way.

It is also hoped that SUMMR will be of benefit to the providers and maintainers of Linked Data datasets through the adoption of SUMMR (as a whole or aspects of). SUMMR has been shown to be beneficial to the DBpedia dataset through the use of the SUMMR Interlink Validation Tool. The SUMMR Interlink Validation Tool is a free, open-source tool, which can be used for any Linked Data dataset for interlink category mapping validation. It is available for the providers and maintainers of Linked Data datasets to gain the benefit, of interlink category mapping validation that SUMMR offers.

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Appendix A. SUMMR Use Case Template Examples

In Chapter 5, two examples of SUMMR use case templates were provided. These examples were of SUMMR Use Case Templates 1 and 5. In this appendix, examples of the remaining four SUMMR use case templates are provided.

SUMMR Use Case Template 2:

Figure A-1 displays an example of SUMMR Use Case Template 2 specialised for SCMR. This template is concerned returning the source and target properties and any transformation properties of SCMR vocabulary transformation category mappings that adhere to certain search criteria. The criteria that needs to be specified in this example template are specified in the $SEARCH_CRITERIA variable. The $SEARCH_CRITERIA variable will be a string. The idea is that a keyword will be specified in this variable so existing mapping that contain that keyword within their source and target properties can be discovered so that the source and target properties and any transformation properties of the mappings can be returned.

01: PREFIX sp: <http://spinrdf.org/sp#>

02: PREFIX scmr: <https://www.scss.tcd.ie/~meehanal/scmr>

03: SELECT ?source_properties ?target_properties

?transformation_info

04: WHERE { ?mapping scmr:spinRepresentation ?rep.

05: ?rep sp:where/rdf:rest*/rdf:first ?s. 06: ?rep sp:templates/rdf:rest*/rdf:first ?t. 07: OPTIONAL {?rep sp:where/rdf:rest*/(rdf:first)/(sp:expression|sp:arg1|sp:ar g2|sp:arg3)*/(a*) ?trans. 08: ?trans ?pt ?transformation_info . } 09: ?s ?p ?source_properties. 10: ?t ?p1 ?target_properties.

11: FILTER( REGEX( STR(?source_properties) ,

$SEARCH_CRITERIA ) || REGEX( STR(?target_properties) ,

$SEARCH_CRITERIA ) ) }

Figure A-1. Example of SUMMR Use Case Template 2 specialised for SCMR. SUMMR Use Case Template 3:

Figure A-2 displays an example of SUMMR Use Case Template 3 specialised for SCMR. This template is concerned with discovering mapping paths within SCMR vocabulary transformation category mappings. The template will return the source properties of one set of mappings and the target properties of another set of mappings where a mapping paths have been discovered between the two sets of mappings. The

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returned source and target properties can then be used to create new mappings. The criteria that need to be specified in this example template are specified in two variables.

The $SOURCE_DATASET_DOMAIN and the $TARGET_DATASET_DOMAIN

variables will both be stings, indicating the domain URI of the source and target that mapping paths are to be discovered for.

01: PREFIX sp: <http://spinrdf.org/sp#>

02: PREFIX scmr: <https://www.scss.tcd.ie/~meehanal/scmr> 03: SELECT ?source ?target

04: WHERE {?mapping scmr:spinRepresentation ?rep.

05: ?rep sp:where/rdf:rest*/rdf:first ?s.

06: ?s ?p ?source.

07: FILTER ( REGEX( STR(?source), $SOURCE_DATASET_DOMAIN ))

08: ?rep sp:templates/rdf:rest*/rdf:first ?t.

09: ?t ?p1 ?intermediate_dataset.

10: ?mapping1 scmr:spinRepresentation ?rep1.

11: ?rep1 sp:templates/rdf:rest*/rdf:first ?t1.

12: ?t1 ?p2 ?target.

13: FILTER ( REGEX( STR(?target), $TARGET_DATASET_DOMAIN ))

14: ?rep1 sp:where/rdf:rest*/rdf:first ?s1.

15: ?s1 ?p3 ?intermediate_dataset1.

16: FILTER(?intermediate_dataset = ?intermediate_dataset1)}

Figure A-2. Example of SUMMR Use Case Template 3. SUMMR Use Case Template 4:

Figure A-3 displays an example of SUMMR Use Case Template 3 specialised for SCMR. This template is concerned with discovering back links in SCMR interlink category mappings. The template will first discover interlink category mappings between a source and target dataset, then it will return the source and target properties in reverse order so the target properties can be used as a new source and the source properties can be used as a new target for new interlink category mappings. The criteria that need to be specified in this example template are specified in two variables. The

$SOURCE_DATASET_DOMAIN and the $TARGET_DATASET_DOMAIN

variables will both be stings, indicating the domain URI of the source and target that interlink category mappings that are to be discovered.

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01: PREFIX sp: <http://spinrdf.org/sp#>

02: PREFIX scmr: <https://www.scss.tcd.ie/~meehanal/scmr> 03: SELECT ?new_source ?new_target

04: WHERE { ?mapping scmr:spinRepresentation ?rep.

05: ?rep sp:where/rdf:rest*/rdf:first ?prop.

06: ?prop sp:object ?new_source.

07: ?prop sp:subject ?new_target.

08: FILTER( REGEX( STR(?new_target) ,

$SOURCE_DATASET_DOMAIN ) && REGEX( STR(?new_source) ,

$TARGET_DATASET_DOMAIN ) )

Figure A-3. Example of SUMMR Use Case Template 4. SUMMR Use Case Template 6:

Figure A-4 displays an example of SUMMR Use Case Template 6 specialised for SCMR. SUMMR Use Case Template 6 is identical to SUMMR Task Template 5 as it only contains one mapping maintenance and reuse task – task 5 which is alteration of a mapping. This template is concerned with changing a property in a vocabulary transformation category mapping. In this template, the criteria to specify is the mapping identifier specified as the variable $MAP_ID. The remaining criteria to specify is the property to delete, specified as variable $MAPPING_PROPERTY_TO_DELETE

and the property to insert, specified by the variable

$MAPPING_PROPERTY_TO_INSERT. All variables in this template will be URIs.

01: PREFIX sp: <http://spinrdf.org/sp#>

02: PREFIX scmr: <https://www.scss.tcd.ie/~meehanal/scmr> 03: DELETE {?map_props ?b1 $MAPPING_PROPERTY_TO_DELETE. ?rep scmr:sparqlQuery ?query. }

04: INSERT {?map_props ?b1 $MAPPING_PROPERTY_TO_INSERT. ?rep scmr:sparqlQuery ?new_query}

05: WHERE { $MAP_ID scmr:SpinRepresentation ?rep .

06: ?rep scmr:sparqlQuery ?query.

07: BIND(( REPLACE( ?query, $MAPPING_PROPERTY_TO_DELETE,

$MAPPING_PROPERTY_TO_INSERT )) AS ?new_query )

08: {?rep sp:templates/rdf:rest*/rdf:first ?map_props.}

09: UNION {?rep sp:where/rdf:rest*/rdf:first ?map_props.}

10: ?map_props ?b1 $MAPPING_PROPERTY_TO_DELETE. } Figure A-4. Example of SUMMR Use Case Template 6.

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