The IFCtoLBD Converter Current Status

LDAC Workshop 2018

Mathias Bonduel (KU Leuven & UGent)

Jyrki Oraskari (Aalto University)

Pieter Pauwels (UGent)

Maarten Vergauwen (KU Leuven)

Ralf Klein (KU Leuven)

M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein2

• Introduction§ IFC, the IFC-to-RDF converter and ifcOWL§ BOT/PRODUCT/PROPS§ BIM and Linked Data workflows

• The IFCtoLBD converter• Case study• Conclusion

Content

19/06/2018

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein3

Introduction: IFC

...

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein4

• Drawbacks of using IFC?X Generic reasoning and queryingX Easily extend IFC schemaX Fine-grained linkingX Flexible, easy to use schema

Introduction: IFC

IFC-SPF

ifcXML

EXPRESS

XSD

Instance Schema

No standard querying language1 central schema (not modular)Container exchange (file-based)IFC4 Add2: about 1200 classes

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein5

• Semantic web technology to the rescue!

Introduction: ifcOWL

IFC-SPF

ifcXML

EXPRESS

XSD

Instance Schema

RDF (Abox)

ifcOWL(Tbox)

IFC-to-RDF converter

Endorsed by buildingSMART

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein6

• Drawbacks of using ifcOWL?ü Generic reasoning and queryingü Easily extend ifcOWL schemaü Fine-grained linkingX Flexible, easy to use schema

Introduction: ifcOWL

Reasoning engines + SPARQLWeb ontologies are modularLinked Data: cross-disciplinaryOWL mirror of IFC schema

Complex schema (Tbox) => complex data (Abox)• Negative influence on query writing (overhead)• A lot of redundant triples (incl. geometry)• Hinders usage in web applications

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein7

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein8

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein9

• Need for smaller, modular ontologies: § BOT, PRODUCT, PROPS, etc.

Introduction

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein10

Introduction: workflows

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein11

Introduction: workflows

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein12

• Goal: Convert IFC building models to RDF Abox graphs according BOT/PROPS/PRODUCT§ Less complex graph – same amount of (relevant)

information§ Simplify query writing

• Features:ü Open-source: available on Githubü PROPS: 3 levels of complexityü Modular Abox graphsü No geometry

The IFCtoLBD converter

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein13

IFCtoLBD converter: GUI

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein14

PROPS

BOT

PRODUCT

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein15

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein16

Case study: Duplex House

• IFC model: 2.3 MB in IFC-SPF (IFC2x3 TC1)• ifcOWL Abox graph: 17428.0 KB in Turtle (227143 triples)

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein17

Case study: Duplex House

83% less triples

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein18

Case study: Duplex House

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein19

Case study: Duplex House

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein20

Case study: Duplex House

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein21

IFCtoLBD converter translates IFC to LBD Abox graphsü 83% of triples reduced (all modules and PROPS L3)ü Query writing is simplified using LBD ontologiesü Options to select specific Abox modules (separate or

together)ü Options regarding PROPS ü Open-source software

Conclusion

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein22

• Paths for bot:adjacentZone and bot:adjacentElement• IFC units of properties• IFC attributes: specific property paths• BOT and IFC have different ways of modeling building

topology§ IfcBuildingStorey vs. bot:Storey§ Relation between storey and element in IFC ≠

bot:containsElement or bot:adjacentElement=> Extra class and relation in BOT?

Future work

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein23

References

1. Beetz, J., Van Leeuwen, J., De Vries, B.: IfcOWL: A case of transforming EXPRESS schemas into ontologies. Artificial Intelligence for Engineering Design, Analysis and Manufacturing: AIEDAM 23(1), 89-101 (2009). https://doi.org/10.1017/S08900604090001222. Mendes de Farias, T., Roxin, A.M., Nicolle, C.: IfcWoD, Semantically Adapting IFC Model Relations into OWL Properties. In: Proc. of the 32nd CIB W78 Conference 2015, 27th-29th October 2015, Eindhoven, The Netherlands. pp. 175-185 (2015)3. Pauwels, P., Roxin, A.: SimpleBIM : From full ifcOWL graphs to simplified building graphs. In: Christodoulou, S., Scherer, R. (eds.) eWork and eBusiness in Architecture, Engineering and Construction (ECPPM). pp. 11-18. CRC Press, Limassol, Cyprus (2016)4. Pauwels, P., Terkaj, W.: EXPRESS to OWL for construction industry: Towards a recommendable and usable ifcOWL ontology. Automation in Construction 63, 100-133 (2016). https://doi.org/10.1016/j.autcon.2015.12.0035. Rasmussen, M.H., Hviid, C.A., Karlshj, J.: Web-based topology queries on a BIM model (2017), presented at 5th LDAC workshop. Dijon, France6. Rasmussen, M.H., Pauwels, P., Hvidd, C.A., Karlshj, J.: Proposing a Central AEC Ontology That Allows for Domain Specific Extensions. In: LC3 2017: Proceedings of the Joint Conference on Computing in Construction. pp. 237-244. Heraklion, Greece (2017)7. Terkaj, W., Pauwels, P.: A Method to generate a Modular ifcOWL Ontology. In: Proceedings of the 8th Workshop Formal Ontologies Meet Industry, Joint Ontology Workshops 2017, CEUR Workshop Proceedings. vol. 2050. Bolzano, Italy (2017)8. Terkaj, W., Schneider, G.F., Pauwels, P.: Reusing Domain Ontologies in Linked Building Data : the Case of Building Automation and Control. In: Proceedings of the 8th Workshop Formal Ontologies Meet Industry, Joint Ontology Workshops 2017, CEUR Workshop Proceedings. vol. 2050. Bolzano, Italy (2017)

ContactIng. Mathias Bonduel - PhD researcher @ FWO

Contact: mathias.bonduel@kuleuven.beWebsite: https://iiw.kuleuven.be/onderzoek/sustainable-

buildings/flemishcitiesintransition

Jyrki Oraskari – PhD researcherContact: jyrki.oraskari@aalto.fi

Website: https://people.aalto.fi/jyrki.oraskari

Github repository: https://github.com/jyrkioraskari/IFCtoLBD

19/06/2018 M. Bonduel, J. Oraskari, P. Pauwels, M. Vergauwen & R. Klein24